Manufactured Home Construction and Safety Standards on Wind Standards; Final Rule DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT

SUMMARY: HUD is amending the Federal Manufactured Home Construction and

Safety Standards (FMHCSS) to improve the resistance of manufactured

homes to wind forces in areas prone to hurricanes. Under this rule,

manufactured homes will have to be designed to withstand wind speeds of

up to 110 miles an hour in hurricane-prone areas, in accordance with

design provisions of the American Society of Civil Engineers Standard

ANSI/ASCE 7-88. Also, the Department is making certain other changes to

the standards to ensure that structural assemblies, components,

windows, connectors, and fasteners will be adequate for the area in

which the home is to be placed. The revised standard also requires

exterior roof and wall coverings to be fastened adequately to sheathing

and framing members, to resist higher design wind pressures.

The purpose of this rule is to increase the safety of manufactured

homes, thereby reducing deaths and injuries and extensive property

damage losses in areas where wind-induced damage is a particular hazard

and risk.

EFFECTIVE DATE: July 13, 1994, except that Secs. 3280.403(b) and (e)

and 3280.404(b) and (e) will become effective January 17, 1995. The

incorporation by reference of certain publications listed in the

regulations is approved by the Director of the Federal Register as of

July 13, 1994, except that the incorporation by reference of

publications listed in Secs. 3280.403(b) and (e) and 3280.404(b) and

(e) will become effective January 17, 1995.

FOR FURTHER INFORMATION CONTACT: G. Robert Fuller, Director,

Manufactured Housing and Construction Standards Division, Department of

Housing and Urban Development, 451 Seventh Street, SW., ATTN: Mailroom

B-133, Washington, DC 20410-8000. Telephones: (voice) (202) 755-7430;

(TDD) (202) 708-4594. (These are not toll-free numbers.)

SUPPLEMENTARY INFORMATION:

I. Background

Developmental History

The purpose of the National Manufactured Housing Construction and

Safety Standards Act of 1974 (42 U.S.C. 5401-5426, at 5401) (the Act)

is to reduce the number of personal injuries and deaths and the amount

of insurance costs and property damage resulting from manufactured home

accidents, and to improve the quality and durability of manufactured

homes. Section 604 of the Act confers authority on the Secretary of HUD

to issue, amend, or revoke any Federal manufactured home construction

or safety standard.

Following Hurricane Andrew, the Department conducted field

investigations of the damage experienced in the hurricane by

manufactured housing units, as part of a full-scale review of the

Federal manufactured home standards. The goal of these investigations

and the review of materials and recommendations was to ensure that the

Federal standards provide adequate protection to manufactured home

occupants during high wind conditions. On April 14, 1993, the

Department published a proposed rule (58 FR 19536) that reported the

preliminary conclusions of the Department's efforts, and sought public

comment on changes that the Department was considering for the Federal

standards. The Department also contacted each of the members of the

National Manufactured Home Advisory Council (Advisory Council),

individually, in order to solicit their individual comments on the

proposed wind standards rule, because the proposed timetable for final

publication did not permit convening the Advisory Council. The

individual responses of the Advisory Council members have been

considered as public comments and included in the docket file for this

rule.

On June 9, 1993, the Department announced (58 FR 32316) that the

comment period would be extended to July 9, 1993. The Department has

continued to receive and consider comments well after that date, while

this final rule was being developed. Because the timeframe originally

proposed for the implementation of standard changes was postponed as a

result of public comments and the extension of the comment deadline,

the Department consulted with the National Manufactured Home Commission

and convened the Advisory Council for consultation and to seek

recommendations from the Advisory Council as a whole (see the notice

published at 58 FR 34586 (June 28, 1993)). The Advisory Council met in

Washington, DC, on July 13 and 14, 1993, to discuss wind standards and

other proposals for changes to the standards for manufactured housing.

The recommendations of the Advisory Council as a whole were

included in a resolution. The resolution questioned the sufficiency of

the evidence to support adoption of the proposed rule and recommended

that: (1) The Department undertake negotiated rulemaking or other

comparable process for this standard; (2) the costs of any rule be

considered, both cumulatively and by zones; (3) the Department examine

its legal and regulatory authority with respect to installation, if it

finds that an installation standard would be an appropriate means of

increasing wind safety; (4) the Department consider all nationally

recognized model codes; (5) the Department make available documents

relating to the development of new wind standards; (6) the Advisory

Council be reconvened to review public comments and the Department's

analysis; (7) the Department should promptly complete the process of

updating the wind standards, considering the issues and questions

raised by the Advisory Council and in public comments; and (8) the

Department should prepare an adequate regulatory impact analysis upon

which it can support the decisions to be made on implementation of new

standards.

The Department has considered the conclusions and recommendations

of the Advisory Council in developing this final rule and the final

regulatory impact analysis. The regulatory impact analysis is

responsive to several of the Advisory Council's concerns, while this

preamble addresses other points raised by the Advisory Council.

With respect to the other points raised by the Advisory Council,

many commenters also suggested that installation is a crucial factor in

the safety of manufactured homes. The Department agrees that the

installation of manufactured housing units may be an important factor

in the safety of such housing and is initiating a review of the

Department's authority and ability to influence tiedown requirements.

However, the Department does not believe there is any significant

advantage in, or that the public interest would be served by,

reconvening the Advisory Council for the purpose of reviewing the

public comments or the Department's compliance with its statutory

responsibilities in the development of these standards. Nor does the

Department believe there is any advantage to the public interest in

undertaking negotiated rulemaking for these standards because they have

been subject to an extensive notice and comment period and have been

discussed with the Advisory Council, a body representative of the

manufactured housing industry, government, and consumers.

Major Differences From Proposed Rule

As a result of the Department's review of public comments and

consultation with the Advisory Council, at this time the Department has

decided not to pursue substantial changes to the standards in areas of

the country not generally subject to hurricanes (Wind Zone I). However,

the Department recognizes that in many areas of the country the Federal

standards applicable to the design and construction of manufactured

housing are far below standards specified for site-built and modular

housing by State and local codes. Thus, the Department shall initiate a

new review of the standards for the rest of the country, and it expects

to publish proposals for these areas next year.

The Department has also decided not to include in the final rule

the following items that were in the proposed rule:

(1) Maximum dimension of 12'' for roof overhangs;

(2) Lower load duration factor than provided in the 1991 National

Design Specification for Wood Construction (NDS);

(3) Requirement for a 1.5 safety factor to calculate resistance of

anchoring and foundation systems to higher design forces in Wind Zones

II and III;

(4) Manufacturer's design and details for a permanent foundation

system (certified by a registered professional engineer or architect)

applicable to each manufactured home design; and

(5) Shortened period for implementation of the standards after

publication.

Relationship to Energy Rule

On October 25, 1993, the Department published a final rule amending

the Federal Manufactured Home Construction and Safety Standards

(FMHCSS) to include preemptive standards significantly upgrading the

existing energy conservation requirements (58 FR 54975) (Energy Rule).

The effective date of that rule is October 25, 1994.

Several of the provisions to be affected by the Energy Rule are

also affected by the rule published today. Because of the earlier

effective date for those provisions in today's rule, the Department

will publish technical amendments to the Energy Rule, before the

effective date of that rule, that also will reflect the new

requirements imposed under today's rule. In some minor instances, the

changes adopted in today's rule already include requirements that

otherwise would have been imposed upon the effective date of the Energy

Rule. Those changes are identified further in the section-by- section

analysis later in this preamble.

Problem To Be Addressed

Each year significant damage to manufactured housing is produced by

straight winds, hurricanes, and tornadoes. Damage is primarily in the

form of roof failure, loss of roof diaphragm material, connection

failures, and tiedown/foundation failures. The most predictable areas

for wind damage to manufactured housing are those subject most directly

to hurricanes. Last year Hurricanes Andrew and Iniki provided dramatic

examples of the destruction faced by housing in hurricane-prone areas.

The damage to manufactured homes by Hurricane Andrew was so

extensive that many were rendered unrecognizable. Ninety-seven percent

of all manufactured homes in Dade County were totally destroyed, while

only eleven percent of single-family homes were destroyed. The American

Red Cross reported that of the 1,176 licensed and registered

manufactured homes in Homestead, Florida, 1,167 were completely

destroyed. The American Red Cross and FEMA have also reported a total

of 11,213 manufactured homes destroyed in Florida and Louisiana in

Hurricane Andrew, and an additional 3,016 manufactured homes

experienced major damage. Almost 36% of all housing units destroyed

during Hurricane Andrew were manufactured homes.

The loss of these units had implications extending beyond the loss

of the homes and possessions of their owners. These homes, shredded by

the winds, also became dangerous flying missiles, inflicting more

property damage on neighboring structures.

In its October 1992 report on Hurricane Andrew, the Federal

Emergency Management Agency (FEMA) stated that, ``in all areas, mobile

homes (manufactured housing) were most susceptible to damage or

destruction. Many mobile homes imploded from the wind loads of

Hurricane Andrew. In coastal areas, where mobile homes were properly

`cradled' and elevated, the cradled foundations remained intact, but

the mobile homes mounted to these foundations were often heavily

damaged or destroyed.''

Concerns for potential losses during high winds in coastal and

other areas were identified previously in a May 1991 report by the

Federal Emergency Management Agency (FEMA), which predicted that the

United States can expect more hurricanes of greater intensity during

the 1990s and early 2000s than it has experienced in recent years.

Furthermore, estimates suggest that by the year 2010 the population

density on Florida's coasts will have increased about 130 percent from

the 1988 level. Moreover, as the national population ages, an

increasing percentage of coastal inhabitants will probably be older

individuals, a group more likely to occupy manufactured houses. The

American Association of Retired Persons (AARP) reports that 40 percent

of the purchasers of new manufactured homes are at least 50 years old.

The elderly can be more difficult to evacuate and may be more prone to

be injured during periods of extreme high winds.

The technology for achieving economical wind resistant designs in

housing is available. It involves calculations of risk for extreme

wind-prone coastal areas and the establishment of construction

standards based upon these risk calculations. Through use and

implementation of this approach, risks of injury and death can be

minimized and economic loss limited to acceptable levels in coastal

areas subject to high winds.

In determining a course of action to address these issues, the

Department had to balance two competing concerns: (1) The need to raise

manufactured housing standards, to protect individuals, their homes,

and their neighbors from future high winds; and (2) the need to

preserve the affordability of a key source of low-cost housing. This

rule is the result of the Department's decision to improve protection

of homeowners in hurricane- prone areas as soon as possible, but to

delay making changes to the standards in lower wind-risk areas, in

order to give adequate consideration to cost factors. Although the

changes are expected to increase costs to consumers in the high-wind

areas, the Department has concluded that the increases are justified,

because the improved standards will significantly reduce future losses

to occupants and the public by strengthening the features that make

manufactured homes vulnerable to damage and destruction in high winds.

Perhaps more importantly, the improved standards may help avoid the

inestimable costs of devastation to people's lives and emotional health

and to the communities, in the likelihood that another powerful

hurricane hits a community of manufactured homes in the hurricane-prone

regions of the country.

Field Investigations--Hurricane Andrew

Among the major deficiencies contributing to manufactured housing

damage in Hurricane Andrew were inadequate connections between exterior

roof or wall coverings and supporting sheathing or framing and between

walls, roofs and floors. In particular, losses of roof coverings were

widespread, and were considered by some to be the first mode of failure

for manufactured homes damaged in Hurricane Andrew. Other roof-related

damage was due to loss of sheathing, failure of connections, or a

combination of these problems. Numerous failures of uplift straps also

occurred, when the staples pulled out through the metal straps,

permitting the straps to tear away from the members to which they had

been fastened. In some cases, entire sections of roofs were blown away.

Another common area of failure was loss of exterior wall siding.

Metal or plastic siding used in manufactured housing was readily

damaged or penetrated by flying debris during the high winds in

Hurricane Andrew. Loss of roof or wall cladding allows the building to

be penetrated by the weather and has far-reaching consequences beyond

the area of envelope integrity.

As a result of these losses, and damage to windows and doors, there

was significant water damage and deterioration to many manufactured

homes. In addition, failure of coverings or attachments to the

manufactured home structure also caused missile-type damage to other

homes.

Other losses were precipitated by prior deterioration around

windows and doors that had allowed moisture to enter, thereby weakening

the resistance of surrounding wood framing and floor decking.

Apparently this deterioration was a result of inadequate design or

enforcement practices, or a combination of both. In some manufactured

homes the loss of opening protection resulted in increased internal

pressures within the buildings, which contributed to the failure of

interior components including ceilings. In other cases, entire sections

of sliding glass doors on leeward walls were literally sucked out of

their frames because of inadequate resistance of the combined assembly

to the wind forces imposed during Hurricane Andrew.

Edges and corners of roofs and endwalls of manufactured homes

appeared to have been particularly vulnerable to the high wind forces,

according to the damage typically reported in these areas. Structural

failures of endwalls also occurred, but the presence of nearby interior

shearwalls prevented further losses (though not all designs are

provided with interior shearwalls in the vicinity of the endwall).

However, in many other cases, the entire superstructure was completely

removed from the floor system.

Numerous anchor system failures were reported in the areas

subjected to the highest wind speeds. Many of the systems failed due to

improper installation or the type of anchor used. In addition, anchor

capacity appeared to have been reduced further because of the saturated

condition of the soil.

Summary of NIST Report

As part of its review of the adequacy of the Federal Manufactured

Housing Construction and Safety Standards (FMHCSS), the Department

contracted for a study by Dr. Richard D. Marshall of the National

Institute of Standards and Technology (NIST) [Report NISTIR 5189, May

1993]. According to Dr. Marshall and several other investigative

reports, damage to manufactured homes in Hurricane Andrew ranged from

loss of roofing to total destruction. In general, HUD-labeled units

suffered less damage than did pre-HUD units. However, conventional

residential construction adjacent to manufactured home parks performed

better, in some instances significantly better, than did manufactured

homes. Based on wind speed assessments and damage surveys, it appears

that HUD-labeled manufactured homes began to experience damage to roof

and wall coverings at fastest-mile wind speeds of up to 95 mph (43 m/

s), and significant structural damage at wind speeds of from 100 to 120

mph (45 to 54 m/s).

Commonly observed failures included loss of roof membranes and

blow-off of roof sheathing, failure of uplift straps at truss-to-wall

connections where staple crowns pulled through the strap, loss of

cladding on endwalls and near corners where large negative (suction)

pressures developed, loss of appurtenances with resultant missile

damage and damage to the primary house unit at connection points,

complete separation of the superstructure from the floor and chassis

frame, and loss of the complete unit because of the failure of tiedown

straps or the withdrawal of soil anchors. The NIST report also pointed

out that the capacity of the anchors appeared to have exceeded the

marginal resistance of the superstructure, and that if the

superstructure separation failures had not occurred, the number of

anchor systems failures could have been much more widespread.

In almost every case in Florida, some form of anchoring had been

installed. Outside the area of strongest winds, there were relatively

few anchor failures. Within the radius of strongest winds, anchor

failures that were observed involved 2 ft. (610 mm) helical ground

anchors (some embedded in about 3 cu.ft. (0.8 cu.m) of concrete) or

rock anchors into coral. No failures of 4 ft. (1.2 m) helical anchors

were noted. However, it is not clear that any anchors of that length

were actually installed in the area subjected to the highest winds.

Dr. Marshall of NIST compared wind load provisions of the current

FMHCSS with the American Society of Civil Engineers (ASCE) Standard

ANSI/ASCE 7-88, the South Florida Building Code, the Standard Building

Code, and wind design provisions proposed by the Manufactured Housing

Institute. Based on these comparisons of design loads for manufactured

housing units of typical dimension and geometry, considering the

rationale for using importance factors and unreduced pressure

coefficients, and in view of the fact that it is a true consensus

standard, Dr. Marshall concluded that ANSI/ASCEP 7-88 should be the

basis for updating the wind load requirements for manufactured housing.

In addition, since the NIST study only addressed design loads, in the

interest of safety and economy, it was also recommended that

prescriptive requirements of the proposed standard be consistent with

the specified design loads and that testing and analysis to assure this

consistency be conducted.

ASCE 7-88: Consensus Procedures for Development and Adoption

The ASCE, founded in 1852, is the oldest civil engineering

organization in the United States and has a membership of more than

110,000. The ANSI/ASCE Standard 7-88, Minimum Design Loads for

Buildings and Other Structures (November 1990) (ASCE 7-88, in this

preamble), was developed by ASCE based on studies conducted at academic

and research institutions in the United States and other parts of the

world.

ASCE 7-88 is the only truly consensus minimum design load standard

currently available in the United States. The ASCE rules, approved by

the American National Standards Institute (ANSI), require all standards

committees to have a membership balanced between producers, consumers,

building officials, and general interest groups. Each of these groups

represents between 20% to 40% of the committee membership. At the time

ASCE 7-88 was adopted, 89 members were on the standards committee.

The approval or revision of an ASCE standard is an elaborate

process, which involves extensive balloting and resolution of all

negative votes. When a standard is to be adopted, the standards

committee is broken down by expertise into task committees. Those task

committees draft the standard and present it to the full standards

committee for balloting. All objections within the standards committee

are satisfied by one of three ways: (1) the objector agrees to withdraw

the objection; (2) by a vote of 75%, the full committee accepts the

objection and changes the standard; or (3) by a vote of 75%, the full

committee rejects the objection. The full committee then votes on the

standard.

In order for the standard to pass the full standards committee, at

least 65% of the committee membership must vote and 75% of those votes

must be in the affirmative. Moreover, the affirmative votes cannot be

less than 55% of the approved voting membership. After the standard

passes the standards committee, it is issued to the public for further

comment. As in the standards committee, all objections are individually

considered and processed in the same manner (i.e., withdrawn or

accepted or rejected by a vote of 75% of the standards committee).

After a certain cutoff date and after all objections are addressed, the

standard is published as an ASCE consensus standard.

ASCE 7-88: Wind Load Provisions in Model Codes

Building codes in each State or local jurisdiction control the

design and construction of buildings and structures in that

jurisdiction. Most communities in the United States adopt, in large

part, one of the three model building codes: the National Building Code

of the Building Officials and Code Administrators International (BOCA);

the Standard Building Code (SBC) of the Southern Building Code Congress

International, Inc. (SBCCI); or the Uniform Building Code (UBC) of

International Conference of Building Officials (ICBO). Wind load

provisions in these model building codes are based on the ASCE 7-88

standard, but with some modifications.

The ASCE 7-88 standard considers all of the factors that influence

the magnitude of wind loads on a building. In addition to wind speed,

those factors include: (1) Terrain surrounding the building, (2) shape

of the building, and (3) desired safety of the building frame and

components. The model building codes use most of these factors from

ASCE 7-88, but modify some of the factors based on experience; because

of tradition, other factors are not considered.

Some provisions of model building codes are adopted from industry

manuals. The use, adoption, and modification of wind-load factors by

the model building codes result from an attempt to simplify the wind-

load provisions and react to the concerns of affected industries and

special interest groups. In general, these modifications by model code

agencies result in lower design requirements for wind forces than would

be required under ASCE 7-88.

Even with these modifications, final wind loads for most buildings

are fairly consistent in all model building codes. All three of the

major model building codes incorporate the basic wind speed map of ASCE

7-88, and reference the ASCE standard in whole or in part, but either

modify the standard or require additional prescriptive design and

construction provisions. In addition, all three provide the use of ASCE

7-88 as an alternative to be applied at the discretion of the designer.

However, the model building codes do not cover the design or

construction of manufactured housing. The only control local

governments have over manufactured housing and mobile (manufactured)

home parks is through certain zoning regulations, or anchoring, set-up,

or installation requirements. As noted by one commenter (150) and

discussed in the next section of this preamble, incorporation of the

ASCE 7-88 standard will be critical to ensuring continued acceptance of

manufactured housing by local jurisdictions in high wind areas.

Building Codes in Southern Florida

Generally, the local jurisdictions in Florida have adopted

modifications of the SBC or South Florida Building Code (SFBC). As one

of its primary recommendations in the aftermath of Hurricane Andrew,

the 18-member Dade County, Florida, Grand Jury stated that the 35-year-

old South Florida Building Code must be rewritten to duplicate the

tougher, national wind standard of ASCE 7-88. The Grand Jury recognized

ASCE 7-88 as a standard that more adequately reflects the design

strength necessary for windows and doors. In acknowledgment of the

Grand Jury's recommendations, the Dade County Building Code Committee

adopted (effective January 1, 1994) the Wind Loads section of ASCE 7-

88, using Exposures C and D, only. The Grand Jury further recommended

that Dade County officials issue a moratorium on the permanent

replacement of manufactured homes until officials could be assured that

the replacement homes meet the ASCE 7-88 standards. Further, noting

that lower standards are applied to manufactured housing than to

conventional housing, the 1992 Fall Term Grand Jury asserted that ``the

low standard amounted to discrimination against those persons unable to

afford the costs of conventional housing.''

In its Final Report, filed August 4, 1993, the Dade County Grand

Jury referenced the initial Grand Jury findings regarding the

engineering advantages of the ASCE 7-88 standard and commended its

adoption into the SFBC. The Grand Jury reported that:

[T]his additional and essential modification of the SFBC should

provoke a wide-ranging improvement of most of our building designs,

methods and products. It should also result in the building of

structures that will provide greater safety and security during a

hurricane.

In order to protect those living in and near manufactured homes, the

Grand Jury has reiterated the recommendation that a moratorium be

instituted on the installation in the County of any new mobile homes

that do not meet the wind-loading standards of ASCE 7-88.

In addition, the SBCCI, after assessing the damage caused by

Hurricane Andrew, concluded that standards applicable to manufactured

housing need to be reviewed to bring them up to the level of other

construction types, unless society is willing to consider manufactured

homes to be expendable. The SBCCI said that even if manufactured homes

are considered expendable, the issue of the hazard they present to

neighboring buildings and structures needs to be addressed.

Accordingly, they further concluded that steps need to be taken to

strengthen the structural frame, enforce tiedown provisions, and assure

that the installation of homes is done by those who are knowledgeable

in the requirements of the code. Unless these issues are addressed, the

SBCCI believes there will continue to be great costs associated with

hurricane damage.

Improved Anchoring and Foundation Systems

Enforcement of anchoring and tie-down systems for manufactured

housing construction has generally been considered a State or local

government and their building officials' responsibility. Section

3282.303 of the Manufactured Home Procedural and Enforcement

Regulations (24 CFR part 3282) urges, but does not require, State

Administrative Agencies to monitor installation of manufactured homes.

Thus, standards for foundations and anchorings and enforcement of those

standards are not uniform among the States, and in some States are

nonexistent. For example, the State of Florida has statewide laws

related to installation, but enforcement of those laws is left to local

building officials, while Louisiana is one of 23 States that does not

regulate installation of manufactured homes at all.

The National Conference of Building Codes and Standards (NCSBCS),

under contract with the Department, sent a team to inspect manufactured

homes damaged or destroyed by Hurricane Andrew. Their report, dated

September 25, 1992 (Rev. October 1, 1992), evaluated anchoring systems

used in Florida and Louisiana. The team found that virtually all

manufactured homes they saw in Florida had been anchored, but anchors

had failed in most destroyed homes.

Some of the systems that failed were anchors embedded only two feet

into the soil, which were pulled out of the ground by the force of the

storm. Other systems that failed included short anchors embedded in

concrete or driven into the coral. In Louisiana, most manufactured

homes the team saw had no anchoring systems at all, or only had two or

three anchors on each side; less than one-half the number generally

specified by manufacturers' instructions for hurricane zones. Also,

where anchors were installed, most had been installed incorrectly;

often embedded only partially in the ground with 12'' or more

protruding above finished grade.

While the majority of anchoring system failures appeared to result

from improper installation, the NCSBCS Team observed several cases

where the holding capacity of anchors appeared to have been reduced

because of water saturated soil. In order to determine the adequacy of

anchoring systems installed in soil that might be exposed to heavy

rainfall and hurricane force winds, further investigating and testing

of anchors will be conducted by the Department.

Numerous failures reported after Hurricanes Andrew and Hugo and

other previous wind storms support the Department's concerns over

anchoring systems for manufactured housing that are inadequate to

resist probable high wind forces. In addition, as the NIST Report

indicated: ``[i]f superstructure failures had not occurred [in

Hurricane Andrew], the number of anchor system failures might well have

been greater * * *.''

Some field and laboratory testing of commercially available ground

anchor and steel strapping systems has been conducted under a HUD

contract with Wiss, Janney, & Elstner, Inc. (See WJE Report No. 901798,

July 26, 1991, HUD USER--HUD-0005823). The initial test results

indicate that anchors have a significantly lower load resistance

capacity than even the levels required by the current standard.

Resistance or capacity would be even lower if anchors are not installed

in accordance with anchor manufacturer's and home manufacturer's

installation instructions or under saturated soil conditions.

The Department has also been conducting laboratory tests to

evaluate the resistance of manufactured home support and anchoring

systems to lateral wind and seismic forces. After the results of the

laboratory data have been evaluated and compared to the field data, the

Department may propose changes to lower allowable anchor system

resistance values.

In the interim, the Department cautions home and anchor

manufacturers, installers, retailers, insurance companies, lenders, and

State and local government agencies that anchoring should be rated for

specific soil, loading, and installation conditions for which the

anchor is acceptable. Failure to do so may result in anchoring and

tiedown systems which have inadequate ultimate capacity to resist

probable design wind forces.

II. Analysis of Public Comments

Characterization of Commenters

The Department received 1,116 comments in response to the proposed

rule and the notice extending the comment period. Although

approximately 235 of these comments are included in file of the Rules

Docket Clerk as being received under the extended deadline, many of

these were delayed in receipt in the Rules Docket Clerk office because

they were sent first to other offices within the Department.

The great majority of the comments were duplicative or identical

form letters (of the 1,116 total comments, only 75 to 100 included

distinctive comments). The commenters generally can be characterized as

follows:

-- Businesses (including retailers, manufacturers, suppliers, finance

companies, park owners, etc.)--704

--Industry groups (including State and national associations)--24

--Members of Congress (including original correspondence and

transmittals of constituent letters)--245

--Other governmental agencies and representatives (Federal, State, and

local agencies or representatives)--27

--Members of the National Manufactured Home Advisory Council

(individually)--15

--Individuals (including consumers, engineers and other experts,

salespersons, etc., in individual capacities)--80

--Private standards groups--6

--Consumer groups--2

--Tenants groups--1

--Insurance industry--3

--National Commission on Manufactured Housing--1

--DAPIA (Design Approval Primary Inspection Agency)--2

--Correspondence forwarded from White House--2

--Law firms--3

--Other national associations--1

Many of the comments received by the Department and addressed in

the following discussion were common to numerous commenters. Other less

universal comments addressed in the discussion may be referenced by

number in parentheses following a statement. These numbers correspond

to the number given the comment in the file maintained by the Rules

Docket Clerk. Comments filed as received in response to the original

comment period are referenced as numbers 1-882 (#817 was inadvertently

skipped in the numbering sequence), while those in response to the

extended comment period are referenced as numbers

1(2)-235(2).

Comments, Generally

A number of commenters acknowledged the need to update the

Department's standards for manufactured housing. One commenter (77)

welcomed the better publicity and reputation the industry would enjoy

as a result of updated standards. However, many of these commenters

also stated opposition to the specific standards proposed by the

Department.

About two dozen commenters, including consumer and insurance

industry groups, standards organizations, government agencies, and

engineers, generally supported the basic standard proposed (e.g., 17,

55, 76, 137, 145, 150, 197, 633, 12(2), 204(2), 207(2)),

although several of these commenters also expressed concern about

specific cost items. Supporting comments emphasized the importance of

affordable, safe housing, rather than merely affordable housing (17),

and characterized ASCE 7-88 as the only consensus wind standard in the

Country (76, and others).

Procedural Comments

Comment: The 30-day comment period allowed in the proposed rule did

not permit sufficient consideration of the rule and development of

public comments. In addition, the justification for the shortened

effective date that the proposed rule had indicated would apply to the

final rule was not justified by the need to implement regulatory

changes before the 1993 hurricane season.

Response: Because of the numerous requests for longer response

periods from both the public and members of Congress, and because it

was apparent that a rule could not be in place in time for the 1993

hurricane season, the Department has allowed additional time for public

comments and implementation of the final rule. The proposed rule was

published on April 14, 1993, and the comment period was extended to

July 9, 1993.

Because of the Department's desire to consider the full extent of

public response on this rule, the Department has continued to receive

comments regularly while the final rule and regulatory impact analysis

were being prepared and has continued to log and review those comments.

Therefore, in effect, the comment period for this rule has been

approximately 5 months.

To alleviate the concerns relating to the industry's need for ample

time to redesign homes and retool manufacturing facilities, the

Department has decided to extend the effective date originally proposed

for this rule. Accordingly, the rule provides for an effective date of,

at least, 180 days from today's date of publication. Thus, the concerns

of the commenters in these regards have been addressed by the

Department.

Comment: The National Manufactured Housing Advisory Council should

be convened, as required by law, to consider the standards proposed by

the Department.

Response: Despite the infeasibility of convening the Advisory

Council within the timeframe originally proposed for the implementation

of improved standards, the Department made an extraordinary effort to

consult with the individual members of the Advisory Council. The

responses of a number of the individual members of the Advisory Council

have been considered and included in the docket file for this

rulemaking.

Later, because of the Department's extension of the comment period

and recognition that a final rule could not be in place in time for the

1993 hurricane season, the Department immediately convened the Advisory

Council so that it could discuss the proposal as a panel. The resulting

recommendations of the Advisory Council, as a panel, also have been

considered carefully in determining both the scope and the specific

requirements of this final rule. Additional discussion of the

proceedings of the Advisory Council can be found elsewhere in this

preamble.

Comment: Several commenters questioned the impact of the rule on

families, in the context of Executive Order 12606, which requires

consideration of the impact of a regulation on family formation,

maintenance, and general well-being.

Response: In the proposed rule, the Department indicated that the

rule was not subject to review under the Executive Order. The

commenters questioned this position based on information that some

potential consumers would be unable to purchase manufactured homes if

the prices of those homes were raised to cover the costs of the new

standards. To the extent that production cost increases resulting from

this rule will be passed on to consumers, one effect of the rule is

expected to be the loss of marginal consumers from the market. Some of

these marginal consumers will have to find less expensive, rental

housing; some will opt for comparably priced site-built housing.

However, the significance of this result is not a loss of housing, but

a redistribution of the kinds of housing available. Although as a

result some families may lose an ownership option, the general well-

being of families, and society, is served better by ensuring adequate

quality standards for such housing.

Although the Department does not believe this final rule implicates

family concerns within the spirit of the Executive Order, the

Department has analyzed the rule as required under the Order.

Therefore, in the paragraph on Executive Order 12606 under the ``Other

Matters'' section of this preamble, the Department certifies that the

requirements of the Order have been met in the issuance of this rule.

Comment: The proposed rule indicated that manufacturers should

anticipate the contents of the final rule and should prepare to comply

with the more stringent standards soon after publication of the final

rule. This schedule for implementation of the new standards fails to

recognize the need for lead time to design, test, and seek approval of

changes necessitated by the standard changes. In addition, while

personnel resources are concentrated on the redesign requirement,

production personnel may have to be laid off. This problem is

compounded by the possibility that another redesign will be necessary

as a result of the new Federal energy standards.

Response: To a large extent, the Department already has been

responsive to the concerns expressed in this comment by conceding that

the rule will not become effective for 180 days. The Department is

sensitive to the procedural requirements that a manufacturer faces when

undertaking design changes. However, there is no doubt that by the time

this rule becomes effective, all aspects of the industry should have

had sufficient advance notice of the necessary product improvements to

prepare for implementation of the new standards.

Innovative solutions and safer products generally depend on some

commercial incentive. The Department believes, based on the knowledge

of its technical staff, the reports they have reviewed, and some of the

comments received, that those parties involved in the production,

sales, and siting of manufactured housing will be able to comply with

these standards reasonably quickly, when continued sales depend on such

compliance.

Cost Considerations

Comment: The cost impact of the standard changes should be

analyzed, as required by Executive Order 12291 and 42 U.S.C. 5403(f),

and a regulatory impact analysis should be prepared.

Response: As stated in the ``Other Matters'' section of the

preamble of the proposed rule (57 FR 19539), the Department agreed that

it would prepare and submit a regulatory impact analysis before

publication of the final rule, in accordance with established Office of

Management and Budget (OMB) guidance. Although many of the benefits,

and some costs, of increased standards are difficult to quantify for

purposes of such an economic analysis (e.g., loss of life, uninsured

costs, insurance deductibles, and injuries), the Department has

complied with the requirements of Executive Order 12866 (September 30,

1993) and OMB. As noted under ``Significant Regulatory Action'' in the

``Other Matters'' section of this preamble, a final regulatory analysis

based on the provisions in this final rule is available to the public.

However, while economic concerns have always been an important

component of the Department's decisionmaking process and, in this case,

resulted in modification of the rule, the Department stresses that its

statutory mandate to reduce the number of personal injuries and deaths

and the amount of insurance costs and property damage resulting from

manufactured home accidents, and to improve the quality and durability

of manufactured homes, requires that the Department look beyond

affordability issues. In promoting homeownership opportunities for

lower-income persons, the Department strongly believes that such

housing must also be safe. The concern with safety extends beyond the

occupants of the housing, to all those who may be affected by the

failure of such housing to meet minimum performance standards under

reasonably foreseeable conditions. For example, in a Federal Emergency

Management Agency (FEMA) report on ``Building Performance: Hurricane

Andrew in Florida'' (FIA-22, 2/93), cited by commenter 76,

It was observed that the breakup of corrugated metal siding and

roofed buildings such as manufactured homes and pre-engineered metal

frame buildings contributed significantly to the generation of

airborne debris. This was evident from debris damage to nearby

downwind structures.

As stated by another commenter (205(2)): ``The prospect of

reducing the loss of life and property and reducing the cost of

disaster relief efforts from such losses as Hurricane Andrew would

certainly be to the benefit of the entire housing industry and the

individual and corporate citizen taxpayers of the United States.'' In

addition, the upgrades required under this rule also would increase the

ability of the homes to withstand damage during transportation and

installation of the units, and the improved windows would be more

energy efficient (see comment 150).

The Department recognizes the viability of manufactured housing as

a source of affordable housing for many people and will continue to

work with the industry to ensure a quality product at a reasonable

cost. However, the Department will also continue to exercise all of its

statutory responsibilities relating to housing and its occupants in a

manner that serves the optimal societal interests. This final rule is

evidence that the Department agrees with those commenters that said the

savings in storm damage repair, loss of personal property, and

potential personal injury or loss of life, in addition to other

expected benefits, exceeds the cost differential for these new

standards. The Department has also reviewed cost impact figures

provided by numerous commenters during the development of the final

regulatory impact analysis.

Comment: The increased cost of manufactured housing that will be

the result of the more stringent standards may price many consumers out

of the market for unsubsidized housing. A home manufactured to the new

standards will require a higher downpayment, and potential consumers

will find it more difficult to qualify for financing. The level of

regulation proposed would limit consumer choice and would deny

consumers the right to match housing to their budgets (1).

Response: The Department is concerned about the effect of these

standards on the ability of consumers to afford and purchase

manufactured housing. However, because the standards are, for the most

part, performance standards and do not prescribe methods of

construction, the manufactured housing industry can, and the Department

expects will, approach this problem by developing innovative designs,

components, and construction techniques that meet the standards but

maintain the affordability of manufactured homes. The Department has

also removed some of the proposed prescriptive requirements. These

changes from the proposed rule should help maintain the affordability

of manufactured housing while still assuring safety.

As stated by one commenter (215(2)), sacrificing a minimum

reasonable wind standard for manufactured housing so that it can be

more affordable makes as much sense as allowing a car to be sold

without brakes for the same reason. A similar opinion was expressed by

a consumer, who commented (117(2)):

If tougher standards increase the cost of a mobile home by a

fair percentage I believe people will be willing to pay a little

more for better protection. Most of these homes are not second homes

but the principal residence of retirees.

Earlier in the preamble the Department acknowledges the legitimate

concern with affordability, but also notes the importance of safe

housing that protects other societal interests.

Conversely, as noted by commenter 145 (FEMA), ``[t]he disruption of

lives and families resulting from the damage to manufactured housing

often happens to those least able to fully recover.'' Therefore, the

financial impact of insufficient standards also may fall most heavily

on those least able to absorb that impact. The Department agrees with

commenter 215(2) that the poor should not have to accept a lower

safety factor against catastrophic failure of housing than the rest of

society.

Finally, a commenter representing a number of insurance carriers

(17) noted that builder/developer estimates of cost increases for

building code improvements for site-built structures have far exceeded

documented incremental cost increases in the past. The commenter

observed that cost estimates with respect to manufactured housing and

the higher standards proposed by the Department may contain similar

exaggerations. This possibility is discussed by the Department in the

regulatory impact analysis prepared in connection with this final rule.

Comment: In looking at storm damage estimates for purposes of a

cost-benefit analysis, the Department should distinguish damage to

manufactured homes that complied with existing HUD standards from

damage to pre-HUD homes.

Response: As previously discussed, both manufactured homes built

before the imposition of HUD standards and those built after the

standards became effective experienced significant damage during

Hurricane Andrew. Therefore, the numerical breakdown between pre- and

post-HUD standards is not a determinative factor in the Department's

process with respect to the final content of this rule.

However, in its comments on this rule, the AARP (commenter #150)

noted that ``[w]hile more than half of the manufactured homes destroyed

were built prior to implementation of the HUD standards, many of these

older homes were constructed in accordance with American National

Standards Institute (ANSI) Standard A119.1, which had the same wind

load resistance requirements as the current HUD standards.''

Comment: As a practical matter, manufacturers will build their

homes to the most stringent standards that would apply to their sales

areas. Therefore, those manufacturers that would build homes for more

than one zone will build all their homes to accommodate the highest

wind load requirements, and the cost of compliance with the new

standards will actually be higher than the estimates that are based on

numbers of units per Zone (12).

Response: The Department does not discourage voluntary compliance

with standards that are higher than those required. However, the

Department believes that the decision to comply voluntarily with higher

standards will be controlled by the cost of such compliance and the

manufacturer's market demands. Accordingly, such compliance is

questionable and cannot be considered in the regulatory impact

analysis.

Comment: The implementation of new standards will adversely affect

the marketability of existing homes not built to those standards (87),

leading to increased defaults and credit losses (139).

Response: The standards implemented by this rule will not affect

manufactured homes already occupied by consumers. Thus, the resale

market for these existing units generally should not be affected,

except to the extent that prospective purchasers have the financial

resources, realize the construction limitations of the existing units,

and choose to purchase units meeting the new standard or other housing

options. Because prospective purchasers of used manufactured housing

are likely to be in lower income brackets, however, the Department

expects little or no impact on the resale market for manufactured homes

already occupied by consumers.

Comment: The additional cost attributable to increased costs for

lumber is of particular concern (639).

Response: As noted above, the Department is concerned about all

additional costs and the affordability of homes constructed to the new

standards. Any specific concern with lumber costs has been alleviated

because of recent changes in market conditions, which have shown that

high prices being charged for lumber earlier this year were an

aberration. Lumber costs have significantly reduced since original cost

estimates were prepared. In addition, the final rule will permit the

use of the 1991 NDS without exception, which lowers earlier

manufactured housing industry projections of the lumber changes and

estimated costs for complying with the new standards.

Scope of Requirements

Comment: The prescriptive standards in the proposed rule would

eliminate the ability of manufacturers to be innovative in developing

safer and more attractive homes.

Response: A number of the prescriptive standards in the proposed

rule have been removed in the final rule. For those that remain,

manufacturers can utilize 24 CFR 3282.14, to take advantage of the

Department's policy encouraging innovation through alternative

construction.

Comment: Because the proposed rule was largely justified as a

response to damages incurred in hurricane-prone areas, the standards

and time frames contained in the proposed rule should not be applied to

other zones subject to lower wind speeds.

Response: At this time the Department has deleted the proposed

changes to Zone I from the final rule. Therefore, homes designated to

be sited in Zone I must comply with the previous wind standard for

those areas. However, many commenters and the Advisory Council

indicated that the Department should strive to bring the Federal

standards to a level of comparability with conventional housing

standards. The Department will review existing wind standards in the

remaining areas of the country for possible future action.

Choice of Standard

Comment: The Department has not demonstrated that ASCE 7-88 is the

appropriate standard to be adopted for the higher wind loading

requirements. For example, the Standard Building Code may be a more

appropriate standard for the purposes of this rule.

Response: A number of engineers have written in support of the ASCE

7-88 standard, noting that the standard was developed based on

scientific studies performed in wind tunnels, which were subsequently

verified by tests on full-scale structures. By adopting the Southern

Florida Building Code (SFBC), which incorporates the Standard Building

Code, the people of south Florida thought they were protected by one of

the toughest building codes, with respect to wind. However, the wind

load requirements of the SFBC now have been surpassed by other codes

that are based on recent research. For example, the SFBC does not

reflect peak gusts or use pressure coefficients as high as are now

considered suitable. As a result, the SFBC design wind speed of 120 mph

would only correspond to a design wind speed of less than 100 mph for

many elements of the construction. As previously noted in this

preamble, Dade County has adopted (effective January 1, 1994) the wind

loads section of ASCE 7-88, using Exposures C and D, only.

Comment: No model code has adopted the ASCE 7-88 standard. The

Department does not justify its attempt to impose more stringent

standards for manufactured housing than are applied to site-built

homes. It is an abuse of Federal authority to impose standards that go

well beyond any State building code currently in existence (87).

Response: The relationship between the model codes and ASCE 7-88 is

discussed earlier in the preamble in the section on Development and

Adoption of ASCE 7-88. In addition, the Department notes that the ASCE

7-88 standard already is incorporated into its Minimum Property

Standards (24 CFR part 200, subpart S), which apply to certain site-

built housing within the Department's jurisdiction.

The current wind load requirements for manufactured housing for

high wind zones correspond to a wind speed of 80 mph; other types of

housing are subject to much higher design wind speed requirements in

the same high wind areas. Therefore, as noted by the AARP in its

comments (150), adoption of ASCE 7-88 actually will ensure substantial

equivalence of wind design requirements between manufactured and site-

built housing.

Furthermore, Dade, Broward, and Palm Beach Counties in Florida have

adopted ASCE 7-88 (with the 110 mph wind load) for site-built homes,

and the Department believes other coastal jurisdictions will follow.

Model codes also have adopted or are moving toward the adoption of the

ASCE 7-88 standard. In fact, by not including the higher standards for

the remainder of the country (Zone I), a majority of manufactured homes

produced in this country will comply to a standard well below the

building codes currently in existence for site-built housing.

Comment: The Department should recognize ``deemed-to-comply''

standards.

Response: The Department considered the deemed-to-comply standards,

but determined that a performance standard would allow manufacturers

flexibility to be innovative in their approach to compliance with the

standards. Such innovation will reduce the cost associated with strict

adherence to the deemed-to-comply standards.

Comment: The rule expands the ASCE 7-88 definition of ``components

and cladding'' to include exterior coverings and fastenings, and the

limited availability of these materials may make compliance difficult

(221).

Response: The Department has made alternative provisions in the

standard for adequate resistance of exterior coverings to specified

design wind pressure requirements.

Enforcement

Comment: The proposed rule did not address testing issues. The

Department does not specify whether the proposed structural design

changes have been subjected to destruction testing. (144) Although

there is no agreement on a testing protocol, truss suppliers will need

time to retest their many truss designs. (8, 16, and incorporated by

reference in others) The need to test many types of siding, siding

gauges (thicknesses), and accessories, fasteners, and fastener patterns

also may lead to tooling changes, which will require more time. (9)

Response: Testing will continue to be evaluated under the DAPIA

review process, which is not revised by this rule. However, the

Department has extended, to 180 days (or, for some provisions, one

year) from today's publication of the rule, the implementation schedule

for the new requirements, in order to give producers sufficient time to

comply with the standards.

Comment: The existence of multiple wind zones and corresponding

requirements within a single State creates difficulties with respect to

enforcement, as well as with production. It is not clear who bears the

responsibility for monitoring the placement of homes within a wind zone

for which they are intended (87, 91, 92, 610).

Response: The Department appreciates the difficulties of enforcing

the standards when multiple zones exist in a single State. Accordingly,

the Department has specifically listed those local governments in the

higher wind zones in each State. Depending on the facts surrounding the

sale of a manufactured home, both the manufacturer and the dealer will

be responsible for assuring that the home will be in compliance with

the standards by siting the home in the proper zone. The State

Administrative Agencies (SAAs) will be informed of the changes

resulting from this rule and will assist the Department in discovering

homes that are sited in noncompliance with these standards.

Anchoring and Tie-Downs

Comment: The change in lease communities could be revolutionary, as

homes become more permanent in nature (122) and homes are taxed more as

real, rather than personal, property. Generally, lessors are required

to restore the site to its original condition when they move. This

requirement, and the relocation of utility connections, would be made

more difficult with more permanent foundations. In addition, the FHA

Title II allowance for installation would not be sufficient for the

additional costs of permanent foundations (146, and others).

Response: The Department has evaluated these comments and has

removed the design requirement for a permanent foundation. However, the

Department remains concerned that some form of strengthened tiedown

system may be necessary to protect homes adequately in high wind areas.

Thus, the Department will be reviewing the issue of permanent

foundations and other strengthened anchoring systems in conjunction

with regulatory action on wind resistant design and construction

requirements for the remainder of the country.

Comment: The impact of the new Wind Standards can be adversely

effected if there is inadequate enforcement and monitoring of the

placement of homes to assure that only homes that have been designed

for the wind load requirements of the Zone are permitted to be sited.

There is a need for better local inspection; the home is only as good

as its anchoring system (149). There is compelling evidence that much

of the damage from Hurricane Andrew was attributable to the lax

enforcement of State and local building codes, including anchoring

requirements, rather than to inadequate standards (80, 122). Similarly,

the main problem with manufactured homes is the proper installation of

anchoring equipment, which the Department cannot regulate (100).

Response: Although the use of tiedowns was widespread in the areas

affected by Hurricane Andrew, indicating some attempt to comply with

codes, the tiedowns generally performed very poorly. None of the

tiedowns observed was certified in accordance with code requirements.

The Department is reviewing the authority to regulate installation of

manufactured homes and is exploring ways to encourage States and

localities to adopt and enforce more stringent anchoring requirements.

The Department also is reviewing appropriate methods, including a

disclosure requirement, to inform consumers about the installation of

the home in a manner that achieves the highest wind protection

performance for the home's design.

Meanwhile, the Department will be contacting the Governors of all

States, and in particular States where the wind risk is the greatest,

to advise the Governors of the changes in the wind standards and the

need for each State to establish installation standards and a system of

enforcement and monitoring.

Comment: Typical ground anchors performed adequately in Hurricane

Andrew (14(2)-17(2), 73(2), 88(2), and others). If

given enough time, ground anchor manufacturers can develop an anchoring

system that is comparable to a permanent foundation system (29).

Response: With very few exceptions, manufactured homes in the path

of Hurricane Andrew were destroyed by the resulting wind forces. The

lack of adequate attachment of single or double-wide units to ground

anchors was a major factor in loss of units. The chassis of some units

could be found some distance away from their original site. However, in

some cases the anchors did hold the floor of the unit down while the

``box'' of the structure was torn away by the high winds. For this

reason, there is justification for increasing the strength of the

structure by this final rule.

The effective date of these new requirements will now be at least

180 days from today. The Department agrees that innovative anchoring

systems comparable to permanent foundations systems can be developed;

however, anchor manufacturers are cautioned regarding the resistance

capacity of auger-type anchors presently used for installing

manufactured homes, when those anchors are subject to high winds and

ensuing saturated soil conditions. The Department's tests show

substantially less resistance than required by 24 CFR 3280.306(f), even

when tested under dry soil conditions.

Comment: Substantially increased siting requirements would be a

problem especially for retirees in land-lease communities and for

minority owners who reside on ``heir property'' and cannot secure clear

title to their site (672).

Response: Alternative anchoring systems that are expected to

provide the required resistance to high wind forces are already

available in the market. The Department believes that if siting

requirements are increased by State and local governments, the

manufactured housing industry will likely develop ways to accommodate

siting in land-lease communities.

Technical Comments

Comment: The Department has not justified its proposal to require a

lower load duration factor for designing wood members and fastenings to

resist wind forces than is specified in the 1991 edition of the

National Design Specification for Wood Construction (NDS) published by

the American Forest and Paper Association (AFPA).

Response: The Department agrees that the higher factor of 1.6 in

the NDS has been justified by research completed by AFPA for wood

members subjected to short duration loads of 10 minutes or less. This

is generally recognized as the maximum period for exposure of

structures to wind forces. In addition, the 1991 NDS has already been

adopted without exception by certain model code agencies. However,

cyclic testing to evaluate fasteners and connectors has not yet been

completed. Preliminary results suggest that a higher load duration

factor may be appropriate. Therefore, the Department will accept the

higher load duration factor of 1.6 on an interim basis and will

recognize the 1991 NDS without exception in this final rule. The

Department intends to monitor this research and may propose a different

load duration factor for fasteners and connectors in the future,

subject to the research and test results.

Comment: There is no basis for the 12'' limitation and prescriptive

requirements for eave and cornice projections; their implementation

would inhibit design innovations.

Response: While longer eave and overhang projections will subject

trusses, fasteners, and connectors to significant increases in design

loads, and thereby increase their likelihood of failure under extreme

wind conditions, the Department agrees that the provision should be

removed because it does restrict innovation, and truss and home

manufacturers are capable of designing roof systems and connections to

resist the higher wind forces. However, manufacturers that use larger

projections than 12 inches are cautioned to review their designs

carefully to assure that all components and fastenings are adequate to

resist the design pressures specified in ASCE 7-88 or the table in

Sec. 3280.304.

Comment: The prescriptive requirements for sidewall-to-roof and

floor connections using steel strapping or brackets should be replaced

with performance criteria that permit the use of alternative methods of

connection, such as structural sheathing that overlaps the roof and

floor.

Response: In general, the Department agrees that the use of

performance-based standards is preferred. However, on-site

investigations of the damage from Hurricane Andrew revealed that

current designs using 30 gage straps failed. Based on the above

information, the Department has retained the prescriptive requirement

for strapping in high wind areas, but will permit to be used a

combination of strapping and structural sheathing that overlaps the

roof or floor, instead of only steel straps or brackets, provided the

sheathing and its fastenings are demonstrated by calculations or tests

to have equivalent strength and resistance to the design wind uplift

forces.

Comment: The use of the 1.5 factor of safety for design of

anchoring systems is not consistent with ASCE 7-88.

Response: The Department concurs that there is no provision in the

ASCE 7-88 standard for increasing the wind pressures for the design of

anchoring systems to resist overturning and sliding forces. Therefore,

the anchoring design provisions for Wind Zones II and III, which are

based on the ASCE 7-88 requirements, will not require the application

of the 1.5 factor of safety to be applied to the design wind drag and

uplift pressures. However, the 1.5 factor of safety will continue to be

required for calculating the required resistance of anchoring systems

for Wind Zone I, since the design lateral and uplift wind forces remain

based on the current standard, which is lower than all model building

codes.

Comment: The Department should clarify whether new wind uplift

design loads in the Table (in Sec. 3280.305) are gross or net uplift

loads.

Response: The uplift wind loads in the table are the full or

``gross'' loads. Gravity or dead loads may be deducted from these loads

when calculations are prepared using the design pressures in the table.

Comment: Existing truss testing procedures in Sec. 3280.402(c)(2)

should be clarified as to: (1) The acceptability of existing inverted

truss testing procedures for evaluating new wind uplift design loads;

(2) whether vertical live and gravity roof load testing must still be

conducted with trusses in the upright position when uplift forces are

higher than downward loads; and (3) whether eave loads are to be

applied simultaneously with roof uplift loads.

Response: (1) The inverted test method may continue to be used on

an interim basis while the Department evaluates results of an industry

study to compare results of the existing test method, which applies

load to the bottom chord of the truss, to results obtained from

applying the load to the top chord of the truss. (2) Testing must

continue to be conducted in the upright position, because the loads are

applied to different members (chords) of the truss. (3) Uplift loads

are to be applied to truss eave projections when uplift loads are

applied to the truss bottom chords during each loading phase required

by Sec. 3280.402(c)(2).

Comment: A new provision should be added requiring a professional

engineer to prepare and certify wind load designs and calculations.

Response: The Department will consider this suggestion for future

rulemaking on wind load requirements.

Comment: Special standards should be required for asphalt shingle

performance in high wind areas, because of the large number of failures

that occurred in Hurricane Andrew and ensuing structural and water

damage caused by these failures.

Response: The asphalt shingle industry research is not yet

completed in this area. As an interim step, this final rule requires

each shingle to be secured with two additional fasteners and

underlayment to be cemented to the roof decking.

Comment: Testing requirements should be specified for windows and

doors to avoid missile damage in high winds. Safety standards can be

enhanced without affecting affordability, by requiring operating

shutters and proper anchoring (88(2)).

Response: The Department encourages manufacturers to provide

shutters or protective devices for homes in Wind Zones II and III.

Under this rule manufacturers will be required, at a minimum, to

provide instructions for an appropriate method of shutter or cover

installation to protect the home, and to include shutter information on

the data plate. The instructions must provide a method for protecting

the windows and doors that is capable of withstanding design wind

pressures without taking the home out of conformance with the

standards. The application of shutters does not do away with the need

for testing the doors or windows they protect.

Comment: A requirement should be added for the use of perforated

metal straps at the marriage line of the roof, between sections of

doublewides, to transfer wind forces from the windward to the leeward

side of the roof.

Response: As part of its continuing evaluation of wind design

requirements, the Department will assess the merits of this proposal.

Comment: The Department needs to establish standards to regulate

the addition of appurtenances to manufactured homes, such as porches,

carports, and canopies, which experienced a large number of failures in

Hurricane Andrew. The danger to occupants is further increased because

the rule does not address the effect of dangerous appurtenances (52,

65, 122).

Response: Under 24 CFR 3282.8(j) the standards currently do not

govern add-ons, as long as the add-on doesn't affect the ability of the

home to comply with the standards. However, as noted in that section,

the Secretary has authority to promulgate standards for some add-ons.

Accordingly, the Department is examining its authority in this area and

may establish requirements in the future. In the interim, HUD

encourages all States to establish standards covering the construction

and attachment of these kinds of appurtenances to manufactured homes.

Comment: Exposure D in ASCE 7-88 should be used for coastal

shoreline areas.

Response: Under this rule manufacturers are required to include on

the data plate a statement that units designed to meet the minimum

standards in this rule should not be located within 1500 feet of the

coastline in Zones II and III. By this statement, the consumer is

alerted that only units designed and anchored according to the higher

design standards specified for coastal areas in ASCE 7-88 should be

placed along the coastline.

Comment: ``Wind safety'' is a misnomer; the science of weather

forecasting allows ample notice of dangerous storms to permit

evacuation (296-314). Homeowner safety is better served by evacuation

in high winds than from protection afforded by the manufactured home

structure. If a manufactured home is purported to be designed and

constructed to withstand higher wind speeds, occupants may be less

likely to evacuate the homes at the approach of a dangerous storm.

Response: The Department agrees that if it is safe to do so,

homeowners should attempt to reach a shelter capable of resisting high

winds. However, without the imposition of these enhanced Wind Safety

Standards, the numbers of deaths and injuries attributable to the

inadequate performance of manufactured homes in high winds will

continue unabated. In addition to reducing deaths and injuries, the

Department's statutory responsibilities require the implementation of

higher wind standards to reduce the insurance cost and amount of

property damage resulting from manufactured home accidents and

improvement of the quality and durability of manufactured homes. The

Department believes that these higher wind standards will fulfill those

responsibilities.

Comment: The NIST study cited by the Department does not fault the

performance of trusses; increasing the uplift requirements would not

improve the quality of assembly. The problems associated with

manufactured housing are related more to fasteners and tiedowns

(13(2)).

Response: The field studies referenced in the NIST Report

identified numerous roof system failures that were generally due to

failure of the end connections between the trusses and the sidewalls.

However, even if the trusses had been properly connected to the

manufactured home structure, the Department believes that trusses not

designed to resist the uplift pressures referenced in this rule still

may have failed. Therefore, in this final rule the Department has

retained the proposed increased design requirements for roof trusses.

Other Specific Comments

Comment: The Department is encouraged to coordinate this rule with

a review of seismic and flood loads, especially with respect to

foundation and attachment designs (25).

Response: The requirements in the proposed rule for a permanent

foundation design have been eliminated in this final rule. However, as

the Department continues to review the issue of adequate anchoring/

foundation systems for manufactured homes, it will also review these

other considerations.

Comment: There are not enough DAPIA personnel in the HUD system to

review and approve design changes within the time provided for the

effectiveness of this rule (83, 124, 136, 179).

Response: The Department has agreed to delay the effectiveness of

the new requirements for 180 days, which should allow sufficient time

for the DAPIA process, as well.

Comment: The Department should consider requiring the DAPIA

approval stamp on all pages of a manufacturer's installation

instructions (48).

Response: The final rule continues to require that the manufacturer

provide installation instructions certified by a registered

professional engineer indicating at least one acceptable system of

anchoring (24 CFR 3280.306(b)). However, the Department will consider

the suggestion to require a DAPIA approval stamp on each page of the

manufacturers' installation instructions when developing future

revisions to the Manufactured Home Procedural and Enforcement

Regulations (24 CFR part 3282).

Comment: Some explanation is needed about the effect of the new

standards on ``B'' letters, interpretative bulletins, and compliance

determinations (122).

Response: This new standard supersedes any portions of ``B''

letters, interpretative bulletins, and compliance determinations that

are in conflict with this standard.

Comment: If the higher standards are adopted, manufacturers will

prefer to build modular homes that meet the necessary State standards.

Response: Manufacturers are free to channel their activities in any

way that best responds to market forces. In the development of the

regulatory impact analysis, the Department has accounted for the cost

of potential lost business. To the extent that manufacturers could

redirect their production to alternative housing, the costs of the

higher standards would be lessened. However, as noted above, the

Department believes that the trend in State standards also will be to

stricter wind standards. Therefore, while manufactured homes may

experience a price increase because of these standards, they will be

affordable relative to site-built homes meeting the higher State-

imposed standards.

Comment: The Department should prepare a brochure on hurricane

awareness and windstorm protection.

Response: As noted in the discussion on Improved Anchoring and

Foundation Systems earlier in the preamble, the Department is reviewing

what would be an appropriate consumer information disclosure

requirement on installation. As part of that review, the Department may

consider requirements on the disclosure of general information relating

to high winds and hurricanes, and may coordinate with FEMA on the

development of a brochure on hurricane awareness and protection for

occupants of manufactured homes.

(Note: Other specific comments that have become moot as a result

of the decision not to proceed with changes in Wind Zone I and

requirements relating to a permanent foundation system are not

addressed in this preamble.)

III. Description of Changes to the Standards

Because of the risk of loss of life to building occupants and the

extraordinary loss of property due to Hurricane Andrew, the Department

has determined that it is necessary to amend the Federal Manufactured

Home Construction and Safety Standards (FMHCSS) to raise the level of

wind resistance standards, especially in areas subject to high winds.

Specifically, the Department is amending the FMHCSS to include a Basic

Wind Zone Map that is based on the map contained in the incorporated

standard ASCE 7-88, ``Minimum Design Loads for Buildings and Other

Structures.''

The revised map contains a more concentrated area for the 100 mph

wind zone than was specified in the current standard or the proposed

rule. The boundary between Wind Zones I and II follows the 90 mph

isotach on the ASCE 7-88 basic wind speed map, while the boundary

between Wind Zones II and III remains the 100 mph isotach indicated in

the proposed rule. The design wind speeds for high wind areas are

designated as 100 mph for Wind Zone II and 110 mph for Wind Zone III.

This rule does not change the current design wind speed for Wind Zone

I.

Based on the revised map, this final rule enumerates the States,

Territories, and local governments in which the more stringent

standards will be applicable. The enumerated areas are those that the

Department has determined to be at least partially within the higher

wind zones demarcated on the revised map. The Department also will

monitor local building code requirements and will consider adoption

through rulemaking of requirements for manufactured homes that are

comparable to any more stringent requirements established for site-

built homes by a State or local building authority.

The current wind standard for manufactured housing is considered

inadequate because it addresses only positive (external) design wind

pressures for walls, components, windows, and cladding, without

specifying that designs must take into account the effect of negative

pressure (suction) on these building elements, as well as internal

pressures on walls and roof/ceiling systems. The formulae used in ASCE

7-88 also include other factors, which account for higher uplift forces

on roof eaves, ridges, overhangs, and corners. These and other issues

are now addressed in high wind areas by requiring the manufactured home

structure, components, and cladding to be designed to resist design

wind forces for Exposure C, as specified in ASCE 7-88.

Requirements for structural assemblies, components, connectors,

fasteners, and a number of other areas will be strengthened so that

parts and portions of the home will be able to resist the same wind

forces as required for site-built and modular housing. In addition, the

increased wind loads required by this rule are applicable whether

structural systems, components, or other aspects of the design are

substantiated by engineering analysis or by suitable load tests (see

subpart E of part 3280). The revised standards also require that the

ground anchoring and foundation support systems continue to be designed

by a registered engineer or architect in a manner adequate to withstand

the higher wind forces specified.

III. Section-by-Section Analysis

The Secretary has determined that the following changes should be

made to the standards:

(1) Section 3280.4--The American Society of Civil Engineers (ASCE)

is added to the list of organizations issuing standards that are

incorporated by reference. The street addresses are corrected for two

other organizations listed.

(2) Section 3280.5--Technical and conforming corrections are made

to standardize paragraph designations to Federal Register format and

clarify the information to be included on data plates. The new

requirements also incorporate changes to the data plate adopted in the

Energy Rule (58 FR 54975, 55003) for effect in October 1994, in order

to avoid having inconsistent requirements become effective within a

short time.

The data plate is also being expanded to indicate that manufactured

homes should not be located within 1500' of the coastline in Wind Zones

II and III unless the home and its anchoring or foundation system are

designed for the increased requirements of Exposure D in ASCE 7-88. The

data plate will now also indicate whether the home has been equipped

with storm shutters and, if shutters are not provided, will strongly

recommend that the home be made ready for these devices in accordance

with the method described in the installation instructions.

(3) Sections 3280.302(a)(8), 3280.303(d), 3280.305(c)--The

definition and references to ``hurricane resistive design'' in these

sections are deleted, in favor of the Wind Zone II and III designations

in the revised Basic Wind Zone Map. These changes will result in the

identification of design wind forces and wind speeds for which the home

has been designed, rather than the designation of homes as ``hurricane

resistive.''

(4) Section 3280.304--The incorporated standards are amended to

require that the minimum design loads be based on ASCE 7-88, which

replaces the obsolete ANSI A58.1-1982 standard currently referenced in

this section.

In addition, the National Design Specification for Wood Members

(NDS), incorporated by reference, is updated to the most current

specification issued by the American Forest and Paper Association

(AFPA). Because manufacturers will need to redesign the structure's

resistance to wind forces, the redesign should be accomplished with the

most current design values for wood. Accordingly, the 1991 NDS is

incorporated in its entirety into the standards.

(5) Section 3280.305(c)--The standards are amended to require that

for manufactured homes in high wind areas, the home and each wind

resisting part, including components and cladding, be completely

designed to resist the design wind pressures specified for a 50-year

recurrence level by ASCE 7-88 or the pressures specified in a table of

equivalent design wind load provisions. The Department has designated

three wind zones: Zone I (current wind design requirements for Zone I);

Zone II (design wind speed of 100 mph); and Zone III (design wind speed

of 110 mph).

The Table of Design Pressures in the proposed rule is clarified and

expanded. Editorial revisions to clarify the application of the uplift

pressure requirements for exterior roof coverings, eaves and gables. In

addition, footnotes are included to indicate:

Distributional pressure effects between windward and

leeward walls;

The application of the Table is limited to roof slopes

between 10 and 30 degrees and that horizontal drag pressures need not

be considered for roof slopes under 20 degrees;

The design uplift pressures are the same regardless of

whether they are applied normal to the roof surface or to the

horizontal projection of the roof; and

Exterior roof and wall coverings (excluding glazing),

sheathing, and fastenings need not be evaluated for the design

pressures specified by the Table, when fastened to a 3/8'' structural

rated sheathing and the sheathing is oriented and secured to framing

members in accordance with the fastening schedule specified in the

Table.

The Basic Wind Zone Map is revised by delineating the boundary

between Wind Zones I and II as the 90 mph isotach, and the boundary

between Wind Zones II and III as the 100 mph isotach, on the ASCE 7-88

basic wind speed map. This change will result in certain areas of

existing Wind Zone II being located in the modified Wind Zone I. The

boundary between Wind Zones I and III in Alaska is now designated as

the 90 mph isotach on the ASCE 7-88 map.

(6) Section 3280.305(d)--Interpretative Bulletin D-5-76, under

which the Department has been operating since the late 1970s, is

paraphrased as a new paragraph (2). It clarifies that the deflection

limit for a cantilevered roof is 2 times the length divided by 180.

Eaves and cornices shall be designed for a net uplift pressure of 2.5

times the design uplift wind pressure cited in Sec. 3280.305(c)(1)(i)

for Wind Zone I, and for the design pressures cited in

Sec. 3280.305(c)(1)(ii) for Wind Zones II and III. This change has

already been issued in the Energy Rule (58 FR 54975, 55006), but is

modified in this rule to reflect the standards established for the new

Wind Zones.

(7) Section 3280.305(e)--The standards for fastening of roof

framing to wall framing and wall to floor framing are changed to

require the use of 26 gage minimum steel strapping, or those elements

shall be connected by a combination of strapping and structural rated

wall sheathing that overlaps the roof and floor. Investigations after

Hurricane Andrew revealed that current designs allowed 30 gage straps

with staples for connections of roofs to walls, and walls to floors;

such straps were inadequate to resist even moderate wind forces.

(7) Section 3280.306(a)--The wind design loads used for calculating

resistance of support and anchoring systems to overturning and lateral

movements are revised to include the simultaneous application of the

horizontal drag and uplift forces determined in Sec. 3280.305(c).

(8) Section 3280.306(g)(2)--The standards are amended to require

that the manufacturer's instructions for anchoring equipment be

certified in accordance with the testing procedures found in ASTM

D3953-91, Standard Specification for Strapping, Flat Steel and Seals.

The certification must be made by a registered engineer, architect, or

independent third party testing agency. This is an updated standard for

steel strapping that supersedes the standard originally referenced in

the Federal standard.

(9) Sections 3280.403 and 3280.404--These sections are amended to

require all primary windows, including egress windows and sliding glass

doors, to resist the design exterior and interior wind pressures

specified in Sec. 3280.305(c)(1) for components and cladding. These

requirements are effective one year from today's date of publication of

this rule, as provided in the ``DATES'' section of this preamble. In

addition, manufacturers are required to provide instructions for the

installation of shutters or protective covers, to protect the windows

and doors.

(10) Section 3282.362--Minor conforming changes regarding the data

plate are made in paragraph (c)(3)(i). These changes are explained

under Sec. 3280.5.

V. Other Matters

Significant Regulatory Action

The Director of the Office of Management and Budget has indicated

that this rule could constitute a ``significant regulatory action'' as

that term is defined in section 3(f) of the Executive Order on

Regulatory Planning and Review issued by the President on September 30,

1993. Because an estimation of the new requirements as proposed

indicated that they might have an annual effect on the economy of $100

million or more, a regulatory impact analysis has been prepared for

this final rule. This analysis concludes that the requirements that

will be imposed by this final rule will have an effect on the economy

of less than $100 million, and will have benefits that outweigh the

costs of the additional requirements. This analysis is available for

public inspection during regular business hours in room 10276, Rules

Docket Clerk, Office of General Counsel, Department of Housing and

Urban Development, 451 Seventh Street, SW., Washington, DC 20410.

Regulatory Flexibility Act

The Secretary, in accordance with the Regulatory Flexibility Act (5

U.S.C. 605(b)), has reviewed this rule before publication and by

approving it certifies that this rule will not have a significant

economic impact on a substantial number of small entities. However, the

regulatory impact analysis referenced in the preceding paragraph also

provides relevant analysis and discussion of possible economic impact

on businesses, including small businesses, that must comply with the

provisions of this rule. The rule will establish additional safety

standards for manufactured housing, and therefore would affect the

design and construction requirements in specified areas of the country.

The nature of the rule and its purpose do not present an opportunity

for the Department to vary the rule's requirements so as to reduce

burdens on small entities.

Environmental Impact

At the time of publication of the proposed rule, a finding of no

significant impact with respect to the environment was made in

accordance with HUD regulations in 24 CFR part 50 that implement

section 102(2)(C) of the National Environmental Policy Act of 1969 (42

U.S.C. 4332). The proposed rule is adopted by this final rule without

any change that would be significant for purposes of additional

environmental impact. Accordingly, the initial finding of no

significant impact remains applicable, and is available for public

inspection between 7:30 a.m. and 5:30 p.m. weekdays in the office of

the Rules Docket Clerk at the above address.

Executive Order 12612, Federalism

The General Counsel, as the Designated Official under section 6(a)

of Executive Order 12612, Federalism, has determined that the policies

contained in this rule have federalism implications, and are subject to

review under the Order. Specifically, the rule provides for mandatory

specifications for the construction of manufactured homes that exceed

the standards currently permitted in certain areas of the country.

States and local governments would no longer have the option of

imposing separate requirements that exceed current standards, but are

less stringent than these new standards. However, because the Federal

standards already preempt local discretion in the construction of

manufactured homes, this marginal degree of preemption is not believed

to be significant for purposes of identifying federalism concerns.

Therefore, for these reasons and because of the health and safety

aspects of this rule, the General Counsel has determined that the

federalism implications are not sufficient to warrant the preparation

of a federalism assessment under the Order.

Executive Order 12606, the Family

In the proposed rule, the Department indicated that the rule was

not subject to review under Executive Order 12606, The Family. As

addressed earlier in this preamble, some of the commenters were

concerned about this position. Although the Department does not believe

this final rule implicates family concerns within the spirit of the

Executive Order, the Department has analyzed the rule as required under

the Order.

The General Counsel, as the Designated Official under the Executive

Order, has evaluated the potential of this rule to have a significant

impact on family formation, maintenance, and general well-being.

Although as a result of the more stringent construction requirements

implemented by this rule, some families may lose an ownership option

for housing, the general well-being of families, and society, is served

better by ensuring minimal quality standards for such housing. The

Secretary of Housing and Urban Development has certified that, to the

extent permitted by law, the rule has undergone a Family Impact

Assessment under the Executive Order.

Regulatory Agenda

This rule was listed as Item 1551 in the Department's Semiannual

Agenda of Regulations published on October 25, 1993 (58 FR 56402,

56433) in accordance with Executive Order 12866 and the Regulatory

Flexibility Act.

The Catalog of Federal Domestic Assistance program number is

14.171.

List of Subjects

24 CFR Part 3280

Fire prevention, Housing standards, Incorporation by reference,

Manufactured homes, Reporting and recordkeeping requirements.

24 CFR Part 3282

Administrative practice and procedure, Consumer protection,

Incorporation by reference, Intergovernmental relations,

Investigations, Manufactured homes, Reporting and recordkeeping

requirements.

For the reasons stated in the preamble, parts 3280 and 3282 of

title 24 of the Code of Federal Regulations are amended as follows.

PART 3280--MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS

1. The authority citation for part 3280 is revised to read as

follows:

Authority: 42 U.S.C. 5403 and 5424; 42 U.S.C. 3535(d).

2. Section 3280.4(b) is amended by adding an additional

organization in the listing of organizations issuing referenced

standards immediately following the listing for the Air Conditioning

and Refrigeration Institute (ARI), and revising the addresses for two

previously listed organizations, to read as follows:

Sec. 3280.4 Incorporation by reference.

* * * * *

(b) * * *

AFPA [previously (N)FPA]--American Forest and Paper Association,

1250 Connecticut Avenue, NW., Washington, DC 20036 [previously named

(N)FPA-National Forest Products Association].

* * * * *

ASCE--American Society of Civil Engineers, 345 East 47th Street,

New York, NY 10017-2398

* * * * *

SJI--Steel Joist Institute, 1205 48th Avenue North, Suite A, Myrtle

Beach, SC 29577

* * * * *

3. Section 3280.5 is revised to read as follows:

Sec. 3280.5 Data plate.

Each manufactured home shall bear a data plate affixed in a

permanent manner near the main electrical panel or other readily

accessible and visible location. Each data plate shall be made of

material what will receive typed information as well as preprinted

information, and which can be cleaned of ordinary smudges or household

dirt without removing information contained on the data plate; or the

data plate shall be covered in a permanent manner with materials that

will make it possible to clean the data plate of ordinary dirt and

smudges without obscuring the information. Each data plate shall

contain not less than the following information:

(a) The name and address of the manufacturing plant in which the

manufactured home was manufactured.

(b) The serial number and model designation of the unit, and the

date the unit was manufactured.

(c) The statement:

This manufactured home is designed to comply with the Federal

Manufactured Home Construction and Safety Standards in force at the

time of manufacture.

(d) A list of the certification label(s) number(s) that are affixed

to each transportable manufactured section under Sec. 3280.8.

(e) A list of major factory-installed equipment, including the

manufacturer's name and the model designation of each appliance.

(f) Reference to the roof load zone and wind load zone for which

the home is designed and duplicates of the maps as set forth in

Sec. 3280.305(c). This information may be combined with the heating/

cooling certificate and insulation zone map required by Secs. 3280.510

and 3280.511. The Wind Zone Map on the Data Plate shall also contain

the statement:

This home has not been designed for the higher wind pressures

and anchoring provisions required for ocean/coastal areas and should

not be located within 1500' of the coastline in Wind Zones II and

III, unless the home and its anchoring and foundation system have

been designed for the increased requirements specified for Exposure

D in ANSI/ASCE 7-88.

(g) The statement:

This home has--has not--(appropriate blank to be checked by

manufacturer) been equipped with storm shutters or other protective

coverings for windows and exterior door openings. For homes designed

to be located in Wind Zones II and III, which have not been provided

with shutters or equivalent covering devices, it is strongly

recommended that the home be made ready to be equipped with these

devices in accordance with the method recommended in the

manufacturers printed instructions.

(h) The statement: ``Design Approval by'', followed by the name of

the agency that approved the design.

Sec. 3280.302 [Amended]

4. Section 3280.302 is amended by removing and reserving paragraph

(a)(8).

Sec. 3280.303 [Amended]

5. Section 3280.303 is amended by removing and reserving paragraph

(d).

6. Section 3280.304 is amended by revising the last item listed

under the heading ``Steel:''; by revising the entry ``National Design

Specifications for Wood Construction'' listed under the heading ``Wood

and Wood Products:''; and revising the entry under the heading

``Unclassified:'' in paragraph (b)(1), to read as follows:

Sec. 3280.304 Materials.

* * * * *

(b)(1) * * *

Steel:

* * * * *

Standard Specification for Strapping, Flat Steel and Seals--ASTM

D3953-91.

Wood and Wood Products:

* * * * *

National Design Specifications for Wood Construction, 1991 Edition,

With Supplement, Design Values for Wood Construction, AFPA.

* * * * *

Unclassified: American Society of Civil Engineers Minimum Design Loads

for Buildings and Other Structures--ANSI/ASCE 7-88.

* * * * *

7. Section 3280.305 is amended by adding a new paragraph (b)(4) and

by revising paragraphs (a), (b)(3), (c)(1) and (2); adding a heading

for (c)(3) introductory text; and revising (c)(3) (iii), (c)(4), (d),

and (e), to read as follows:

Sec. 3280.305 Structural design requirements.

(a) General. Each manufactured home shall be designed and

constructed as a completely integrated structure capable of sustaining

the design load requirements of this standard, and shall be capable of

transmitting these loads to stabilizing devices without exceeding the

allowable stresses or deflections. Roof framing shall be securely

fastened to wall framing, walls to floor structure, and floor structure

to chassis to secure and maintain continuity between the floor and

chassis, so as to resist wind overturning, uplift, and sliding as

imposed by design loads in this part. Uncompressed finished flooring

greater than 1/8 inch in thickness shall not extend beneath load-

bearing walls that are fastened to the floor structure.

(b) Design loads-- * * *

(3) When engineering calculations are performed, allowable unit

stresses may be increased as provided in the documents referenced in

Sec. 3280.304 except as otherwise indicated in Secs. 3280.304(b)(1) and

3280.306(a).

(4) Whenever the roof slope does not exceed 20 degrees, the design

horizontal wind loads required by Sec. 3280.305(c)(1) may be determined

without including the vertical roof projection of the manufactured

home. However, regardless of the roof slope of the manufactured home,

the vertical roof projection shall be included when determining the

wind loading for split level or clerestory-type roof systems.

(c) Wind, snow, and roof loads--(1) Wind loads--design

requirements. (i) Standard wind Loads (Zone I). When a manufactured

home is not designed to resist the wind loads for high wind areas (Zone

II or Zone III) specified in paragraph (c)(1)(ii) of this section, the

manufactured home and each of its wind resisting parts and portions

shall be designed for horizontal wind loads of not less than 15 psf and

net uplift load of not less than 9 psf.

(ii) Wind loads for high wind areas (Zone II and Zone III). When

designed for high wind areas (Zone II and Zone III), the manufactured

home, each of its wind resisting parts (including, but not limited to,

shear walls, diaphragms, ridge beams, and their fastening and anchoring

systems), and its components and cladding materials (including, but not

limited to, roof trusses, wall studs, exterior sheathing, roofing and

siding materials, exterior glazing, and their connections and

fasteners) shall be designed by a Professional Engineer or Architect to

resist:

(A) The design wind loads for Exposure C specified in ANSI/ASCE 7-

88, ``Minimum Design Loads for Buildings and Other Structures,'' for a

fifty-year recurrence interval, and a design wind speed of 100 mph, as

specified for Wind Zone II, or 110 mph, as specified for Wind Zone III

(Basic Wind Zone Map); or

(B) The wind pressures specified in the following Table:

Table of Design Wind Pressures

------------------------------------------------------------------------

Wind zone II Wind zone III

Element design wind design wind

speed 100 MPH speed 110 MPH

------------------------------------------------------------------------

Anchorage for lateral and vertical

stability (See Sec. 3280.306(a)):

Net Horizontal Drag1, 2:............ \3\39 PSF \3\47 PSF

Uplift\4\:.......................... \5\-27 PSF -32 PSF

Main wind force resisting system:

Shearwalls, Diaphragms and their

Fastening and Anchorage Systems1, 2 39

PSF 47

PSF

Ridge beams and other Main Roof

Support Beams (Beams supporting

expanding room sections, etc.)..... -30 PSF -36 PSF

Components and cladding:

Roof trusses\4\ in all areas;

trusses shall be doubled within 3'-

0'' from each end of the roof...... \5\-39 PSF \5\-47 PSF

Exterior roof coverings, sheathing

and fastenings\4\,\6\,\7\ in all

areas except the following......... \5\-39 PSF \5\-47 PSF

Within 3'-0'' from each gable

end (overhang at end wall) of

the roof or endwall if no

overhang is provided........... \5\-73 PSF \5\-89 PSF

Within 3'-0'' from the ridge and

eave (overhang at sidewall) or

sidewall if no eave is provided \5\-51 PSF \5\-62 PSF

Eaves (Overhangs at Sidewalls)...... \5\-51 PSF \5\-62 PSF

Gables (Overhangs at Endwalls)...... \5\-73 PSF \5\-89 PSF

Wall studs in sidewalls and

endwalls, exterior windows and

sliding glass doors (glazing and

framing), exterior coverings,

sheathing and fastenings\8\:....... 48

PSF 58

PSF

Within 3'-0'' from each corner

of the sidewall and endwall.... .............. ..............

All other areas................. 38

PSF 46

PSF

------------------------------------------------------------------------

NOTES:

1The net horizontal drag of 39 PSF to be used in calculating

Anchorage for Lateral and Vertical Stability and for the design of

Main Wind Force Resisting Systems is based on a distribution of wind

pressures of +0.8 or +24 PSF to the windward wall and -0.5 or -15 PSF

to the leeward wall.

2Horizontal drag pressures need not be applied to roof projections when

the roof slope does not exceed 20 degrees.

3+ sign would mean pressures are acting towards or on the structure; -

sign means pressures are acting away from the structure;

sign means forces can act in either direction, towards or away from

the structure.

44. Design values in this ``Table'' are only applicable to roof slopes

between 10 degrees (nominal 2/12 slope) and 30 degrees.

5The design uplift pressures are the same whether they are applied

normal to the surface of the roof or to the horizontal projection of

the roof.

6Shingle roof coverings that are secured with 6 fasteners per shingle

through an underlayment which is cemented to a 3/8'' structural rated

roof sheathing need not be evaluated for these design wind pressures.

77. Structural rated roof sheathing that is at least 3/8'' in thickness,

installed with the long dimension perpendicular to roof framing

supports, and secured with fasteners at 4'' on center within 3'-0'' of

each gable end or endwall if no overhang is provided and 6'' on center

in all other areas, need not be evaluated for these design wind

pressures.

8Exterior coverings that are secured at 6'' o.c. to a 3/8'' structural

rated sheathing that is fastened to wall framing members at 6'' on

center need not be evaluated for these design wind pressures.

(2) Wind loads--zone designations. The Wind Zone and specific wind

design load requirements are determined by the fastest basic wind speed

(mph) within each Zone and the intended location, based on the Basic

Wind Zone Map, as follows:

(i) Wind Zone I. Wind Zone I consists of those areas on the Basic

Wind Zone Map that are not identified in paragraphs (c)(2)(ii) or (iii)

of this section as being within Wind Zone II or III, respectively.

(ii) Wind Zone II.....100 mph. The following areas are deemed to be

within Wind Zone II of the Basic Wind Zone Map:

Local governments: The following local governments listed by State

(counties, unless specified otherwise):

Alabama: Baldwin and Mobile.

Florida: All counties except those identified in paragraph

(c)(1)(i)(C) of this section as within Wind Zone III.

Georgia: Bryan, Camden, Chatham, Glynn, Liberty, McIntosh.

Louisiana: Parishes of Acadia, Allen, Ascension, Assumption,

Calcasieu, Cameron, East Baton Rouge, East Feliciana, Evangeline,

Iberia, Iberville, Jefferson, Jefferson Davis, LaFayette, La Fourche,

Livingston, Orleans, Plaquemines, Pointe Coupee, St. Bernard, St.

Charles, St. Helena, St. James, St. John the Baptist, St. Landry, St.

Martin, St. Mary, St. Tammany, Tangipahoa, Terrabonne, Vermillion,

Washington, West Baton Rouge, and West Feliciana.

Maine: Hancock and Washington.

Massachusetts: Barnstable, Bristol, Dukes, Nantucket, and Plymouth.

Mississippi: George, Hancock, Harrison, Jackson, Pearl River, and

Stone.

North Carolina: Beaufort, Brunswick, Camden, Carteret, Chowan,

Columbus, Craven, Currituck, Dare, Hyde, Jones, New Hanover, Onslow,

Pamlico, Pasquotank, Pender, Perquimans, Tyrrell, and Washington.

South Carolina: Beaufort, Berkeley, Charleston, Colleton,

Dorchester, Georgetown, Horry, Jasper, and Williamsburg.

Texas: Aransas, Brazoria, Calhoun, Cameron, Chambers, Galveston,

Jefferson, Kenedy, Kleberg, Matagorda, Nueces, Orange, Refugio, San

Patricio, and Willacy.

Virginia: Cities of Chesapeake, Norfolk, Portsmouth, Princess Anne,

and Virginia Beach.

(iii) Wind Zone III.....110 mph. The following areas are considered

to be within Wind Zone III of the Basic Wind Zone Map:

(A) States and Territories: The entire State of Hawaii, the coastal

regions of Alaska (as determined by the 90 mph isotach on the ANSI/ASCE

7-88 map), and all of the U.S. Territories of American Samoa, Guam,

Northern Mariana Islands, Puerto Rico, Trust Territory of the Pacific

Islands, and the United States Virgin Islands.

(B) Local governments: The following local governments listed by

State (counties, unless specified otherwise):

Florida: Broward, Charlotte, Collier, Dade, Franklin, Gulf, Hendry,

Lee, Martin, Manatee, Monroe, Palm Beach, Pinellas, and Sarasota.

Louisiana: Parishes of Jefferson, La Fourche, Orleans, Plaquemines,

St. Bernard, St. Charles, St. Mary, and Terrabonne.

North Carolina: Carteret, Dare, and Hyde.

(iv) Consideration of local requirements. For areas where local

building code requirements exceed the design wind speed requirements of

these standards, the Department will consider the adoption through

rulemaking of the more stringent requirements of the State or local

building authority.

(3) Snow and roof loads. * * *

(iii) Eaves and cornices shall be designed for a net uplift

pressure of 2.5 times the design uplift wind pressure cited in

Sec. 3280.305(c)(1)(i) for Wind Zone I, and for the design pressures

cited in Sec. 3280.305(c)(1)(ii) for Wind Zones II and III.

(4) Data plate requirements. The Data Plate posted in the

manufactured home (see Sec. 3280.5) shall designate the wind and roof

load zones or, if designed for higher loads, the actual design external

snow and wind loads for which the home has been designed. The Data

Plate shall include reproductions of the Load Zone Maps shown in this

section, with any related information. The Load Zone Maps shall be not

less than either 3\1/2\ in. by 2\1/4\ in., or one-half the size

illustrated in the Code of Federal Regulations.

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(d) Design load deflection. (1) When a structural assembly is

subjected to total design live loads, the deflection for structural

framing members shall not exceed the following (where L equals the

clear span between supports or two times the length of a cantilever):

Floor--L/240

Roof and ceiling--L/180

Headers, beams, and girders (vertical load)--L/180

Walls and partitions--L/180

(2) The allowable eave or cornice deflection for uplift is to be

measured at the design uplift load of 9 psf for Wind Zone I, and at the

design uplift pressure cited in paragraph (c)(1)(ii) of this section

for Wind Zones II and III. The allowable deflection shall be (2 x Lc)/

180, where Lc is the measured horizontal eave projection from the wall.

(e) Fastening of structural systems. (1) Roof framing shall be

securely fastened to wall framing, walls to floor structure, and floor

structure to chassis to secure and maintain continuity between the

floor and chassis, so as to resist wind overturning, uplift, and

sliding as specified in this part.

(2) For Wind Zones II and III, roof trusses shall be secured to

exterior wall framing members (studs), and exterior wall framing

members (studs) shall be secured to floor framing members, with 26 gage

minimum steel strapping or brackets or by a combination of 26 gage

minimum steel strapping or brackets and structural rated wall sheathing

that overlaps the roof and floor. Steel strapping or brackets shall be

installed at a maximum spacing of 24'' on center in Wind Zone II and at

a maximum of 16'' on center in Wind Zone III. The number and type of

fasteners used to secure the steel straps or brackets or structural

sheathing shall be capable of transferring all uplift forces between

elements being joined.

* * * * *

8. Section 3280.306 is amended by revising paragraphs (a)

introductory text and (b); adding a heading for paragraph (c)

introductory text; revising paragraphs (c) (1) through (3) and (d)

through (g) to read as follows:

Sec. 3280.306 Windstorm protection--support and anchoring systems.

(a) Provisions for support and anchoring systems. Each manufactured

home shall have provisions for support/anchoring or foundation systems

that, when properly designed and installed, will resist overturning and

lateral movement (sliding) of the manufactured home as imposed by the

respective design loads. For Wind Zone I, the design wind loads to be

used for calculating resistance to overturning and lateral movement

shall be the simultaneous application of the wind loads indicated in

Sec. 3280.305(c)(1)(i), increased by a factor of 1.5. The 1.5 factor of

safety for Wind Zone I is also to be applied simultaneously to both the

vertical building projection, as horizontal wind load, and across the

surface of the full roof structure, as uplift loading. For Wind Zones

II and III, the resistance shall be determined by the simultaneous

application of the horizontal drag and uplift wind loads, in accordance

with Sec. 3280.305(c)(1)(ii). The basic allowable stresses of materials

required to resist overturning and lateral movement shall not be

increased in the design and proportioning of these members. No

additional shape or location factors need to be applied in the design

of the tiedown system. The dead load of the structure may be used to

resist these wind loading effects in all Wind Zones.

(1) * * *

(b) Contents of instructions. (1) The manufacturer shall provide

printed instructions with each manufactured home specifying the

location and required capacity of stabilizing devices on which the

design is based. The manufacturer shall provide drawings and

specifications certified by a registered professional engineer or

architect indicating at least one acceptable system of anchoring,

including the details of required straps or cables, their end

connections, and all other devices needed to transfer the wind loads

from the manufactured home to an anchoring or foundation system.

(2) For anchoring systems, the instructions shall indicate:

(i) The minimum anchor capacity required;

(ii) That anchors should be certified by a professional engineer,

architect, or a nationally recognized testing laboratory as to their

resistance, based on the maximum angle of diagonal tie and/or vertical

tie loading (see paragraph (c)(3) of this section) and angle of anchor

installation, and type of soil in which the anchor is to be installed;

(iii) That ground anchors should be embedded below the frost line

and be at least 12 inches above the water table; and

(iv) That ground anchors should be installed to their full depth,

and stabilizer plates should be installed to provide added resistance

to overturning or sliding forces.

(v) That anchoring equipment should be certified by a registered

professional engineer or architect to resist these specified forces in

accordance with testing procedures in ASTM Standard Specification

D3953-91, Standard Specification for Strapping, Flat Steel and Seals.

(c) Design criteria. * * *

(1) The minimum number of ties provided per side of each home shall

resist design wind loads required in Sec. 3280.305(c)(1).

(2) Ties shall be as evenly spaced as practicable along the length

of the manufactured home, with not more than two (2) feet open-end

spacing on each end.

(3) Vertical ties or straps shall be positioned at studs. Where a

vertical tie and a diagonal tie are located at the same place, both

ties may be connected to a single anchor, provided that the anchor used

is capable of carrying both loadings, simultaneously.

(4) * * * * *

(d) Requirements for ties. Manufactured homes in Wind Zone I

require only diagonal ties. These ties shall be placed along the main

frame and below the outer side walls. All manufactured homes designed

to be located in Wind Zones II and III shall have a vertical tie

installed at each diagonal tie location.

(e) Protection requirements. Protection shall be provided at sharp

corners where the anchoring system requires the use of external straps

or cables. Protection shall also be provided to minimize damage to

siding by the cable or strap.

(f) Anchoring equipment--load resistance. Anchoring equipment shall

be capable of resisting an allowable working load equal to or exceeding

3,150 pounds and shall be capable of withstanding a 50 percent overload

(4,725 pounds total) without failure of either the anchoring equipment

or the attachment point on the manufactured home.

(g) Anchoring equipment--weatherization. Anchoring equipment

exposed to weathering shall have a resistance to weather deterioration

at least equivalent to that provided by a coating of zinc on steel of

not less than 0.30 ounces per square foot of surface coated, and in

accordance with the following:

(1) Slit or cut edges of zinc-coated steel strapping do not need to

be zinc coated.

(2) Type 1, Finish B, Grade 1 steel strapping, 1-1/4 inches wide

and 0.035 inches in thickness, certified by a registered professional

engineer or architect as conforming with ASTM Standard Specification

D3953-91, Standard Specification for Strapping, Flat Steel, and Seals.

* * * * *

9. Section 3280.403 is amended by revising paragraphs (b) and (e)

introductory text and by adding new paragraph (f), to read as follows:

Sec. 3280.403 Standard for windows and sliding glass doors used in

manufactured homes.

* * * * *

(b) Standard. By January 17, 1995, all primary windows and sliding

glass doors shall comply with AAMA Standard 1701.2-1985, Primary Window

and Sliding Glass Door Voluntary Standard for Utilization in

Manufactured Housing, except that the exterior and interior pressure

tests for components and cladding shall be conducted at the design wind

loads required by Sec. 3280.305(c)(1).

* * * * *

(e) Certification. Except as otherwise indicated in paragraph (b)

of this section, by January 17, 1995, all primary windows and sliding

glass doors to be installed in manufactured homes shall be certified as

complying with AAMA Standard 1701.2-1985 and design wind pressures

specified in Sec. 3280.305.

* * * * *

(f) Protection of primary window and sliding glass door openings in

high wind areas. For homes designed to be located in Wind Zones II and

III, manufacturers shall design exterior walls surrounding the primary

window and sliding glass door openings to allow for the installation of

shutters or other protective covers, such as plywood, to cover these

openings. Although not required, the Department encourages

manufacturers to provide the shutters or protective covers and to

install receiving devices, sleeves, or anchors for fasteners to be used

to secure the shutters or protective covers to the exterior walls. If

the manufacturer does not provide shutters or other protective covers

to cover these openings, the manufacturer must provide to the homeowner

instructions for at least one method of protecting primary window and

sliding glass door openings. This method must be capable of resisting

the design wind pressures specified in Sec. 3280.305 without taking the

home out of conformance with the standards in this part. These

instructions must be included in the printed instructions that

accompany each manufactured home. The instructions shall also indicate

whether receiving devices, sleeves, or anchors, for fasteners to be

used to secure the shutters or protective covers to the exterior walls,

have been installed or provided by the manufacturer.

10. Section 3280.404 is amended by revising paragraphs (b) and (e)

and by adding a new paragraph (f), to read as follows:

Sec. 3280.404 Standard for egress windows and devices for use in

manufactured homes.

* * * * *

(b) Performance. By January 17, 1995, egress windows including

auxiliary frame and seals, if any, shall meet all requirements of AAMA

Standard 1701.2-1985, Primary Window and Sliding Glass Door Voluntary

Standard for Utilization in Manufactured Housing and AAMA Standard

1704-1985, Voluntary Standard Egress Window Systems for Utilization in

Manufactured Housing, except as otherwise indicated in

Sec. 3280.403(b).

* * * * *

(e) Certification of egress windows and devices. Except as

otherwise indicated by paragraph (b) of this section, by January 17,

1995, egress windows and devices shall be listed in accordance with the

procedures and requirements of AAMA Standard 1704-1985 and design wind

pressures specified in Sec. 3280.305.

(f) Protection of egress window openings in high wind areas. For

homes designed to be located in Wind Zones II and III, manufacturers

shall design exterior walls surrounding the egress window openings to

allow for the installation of shutters or other protective covers, such

as plywood, to cover these openings. Although not required, the

Department encourages manufacturers to provide the shutters or

protective covers and to install receiving devices, sleeves, or anchors

for fasteners to be used to secure the shutters or protective covers to

the exterior walls. If the manufacturer does not provide shutters or

other protective covers to cover these openings, the manufacturer must

provide to the homeowner instructions for at least one method of

protecting egress window openings. This method must be capable of

resisting the design wind pressures specified in Sec. 3280.305 without

taking the home out of conformance with the standards in this part.

These instructions must be included in the printed instructions that

accompany each manufactured home. The instructions shall also indicate

whether receiving devices, sleeves, or anchors, for fasteners to be

used to secure the shutters or protective covers to the exterior walls,

have been installed or provided by the manufacturer.

11. Section 3280.405 is amended by adding paragraph (f), to read as

follows:

Sec. 3280.405 Standard for swinging exterior passage doors for use in

manufactured homes.

* * * * *

(f) Protection of exterior doors in high wind areas. For homes

designed to be located in Wind Zones II and III, manufacturers shall

design exterior walls surrounding the exterior door openings to allow

for the installation of shutters or other protective covers, such as

plywood, to cover these openings. Although not required, the Department

encourages manufacturers to provide the shutters or protective covers

and to install receiving devices, sleeves, or anchors for fasteners to

be used to secure the shutters or protective covers to the exterior

walls. If the manufacturer does not provide shutters or other

protective covers to cover these openings, the manufacturer must

provide to the homeowner instructions for at least one method of

protecting exterior door openings. This method must be capable of

resisting the design wind pressures specified in Sec. 3280.305 without

taking the home out of conformance with the standards in this part.

These instructions must be included in the printed instructions that

accompany each manufactured home. The instructions shall also indicate

whether receiving devices, sleeves, or anchors, for fasteners to be

used to secure the shutters or protective covers to the exterior walls,

have been installed or provided by the manufacturer.

PART 3282--MANUFACTURED HOME PROCEDURAL AND ENFORCEMENT REGULATIONS

12. The authority citation for part 3282 is revised to read as

follows:

Authority: 42 U.S.C. 5424; 42 U.S.C. 3535(d).

13. Section 3282.362 is amended by revising paragraphs (c)(3)(i)

(E) and (F) and adding a new paragraph (G), to read as follows:

Sec. 3282.362 Production Inspection Primary Inspection Agencies

(IPIAs).

* * * * *

(c) * * *

(3) * * *

(i) * * *

(E) Reference to the roof load zone and wind load zone for which

the home is designed and duplicates of the maps as set forth in

Sec. 3280.305. This information may be combined with the heating/

cooling certificate and insulation zone map required by Secs. 3280.510

and 3280.511. The Wind Zone Map on the Data Plate shall also contain

the statement:

This home has not been designed for the higher wind pressures

and anchoring provisions required for ocean/coastal areas and should

not be located within 1500' of the coastline in Wind Zones II and

III, unless the home and its anchoring and foundation system have

been designed for the increased requirements specified for Exposure

D in ANSI/ASCE 7-88.

(F) The statement:

This home has ____ has not ____ (appropriate blank to be checked

by manufacturer) been equipped with storm shutters or other

protective coverings for windows and exterior door openings. For

homes designed to be located in Wind Zones II and III, which have

not been provided with shutters or equivalent covering devices, it

is strongly recommended that the home be made ready to be equipped

with these devices in accordance with the method recommended in the

manufacturers printed instructions.

(G) The statement: ``Design Approval by'', followed by the name of

the agency that approved the design.

* * * * *

Dated: January 4, 1994.

Nicolas P. Retsinas,

Assistant Secretary for Housing--Federal Housing Commissioner.

[FR Doc. 94-825 Filed 1-13-94; 8:45 am]

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