Amicus Curiae Brief — American Gas Association, et al., Petitioners v. Department of Energy, et al.

No. 25-879

In The

Supreme Court of the United States

AMERICAN GAS ASSOCIATION, ET AL.,

Petitioners,

v.

DEPARTMENT OF ENERGY, ET AL.

Respondents.

On Petition for Writ of Certiorari to the United

States Court of Appeals for the D.C. Circuit

BRIEF OF AMICI CURIAE

NATIONAL ASSOCIATION OF HOME

BUILDERS OF THE UNITED STATES AND

NATIONAL ASSOCIATION OF REALTORS IN

SUPPORT OF CERTIORARI

Of Counsel:

JONATHAN WACLAWSKI

NATIONAL ASSOCIATION

OF REALTORS®

500 NEW JERSEY AVE, NW

WASHINGTON, D.C. 20001

(202) 383-1248

JWACLAWSKI@NAR.REALTOR

MACKENZIE PAYNE*

THOMAS J. WARD

SABREN WAHDAN

NATIONAL ASSOCIATION

OF HOME BUILDERS

OF THE U.S.

1201 15TH STREET, NW

WASHINGTON, D.C.

20005

(202) 266-8200

MPAYNE@NAHB.ORG

*Amici Curiae Counsel of

Record

i

CORPORATE DISCLOSURE STATEMENT

Pursuant to Supreme Court Rule 29.6, Amicus

National Association of Home Builders of the United

States (“NAHB”) states that it is a non-profit

501(c)(6) corporation incorporated in the State of

Nevada, with its principal place of business in

Washington, D.C. NAHB has no corporate parents,

and no publicly traded stock. No publicly traded

company has a ten percent or greater ownership

interest in NAHB.

Amicus National Association of REALTORS®

states that it is a non-profit, tax-exempt

organization incorporated in the State of Illinois. It

has no corporate parents, and no publicly traded

company has a ten percent or greater ownership

interest in it.

ii

TABLE OF CONTENTS

Page(s)

CORPORATE DISCLOSURE STATEMENT ..... i

TABLE OF CONTENTS ....................................... ii

TABLE OF AUTHORITIES ................................ iv

INTEREST OF AMICI CURIAE ......................... 1

SUMMARY OF ARGUMENT ............................... 3

ARGUMENT ........................................................... 4

I. DOE APPLIANCE STANDARDS IMPOSE

COSTS THAT EXACERBATE AN ONGOING

HOUSING AFFORDABILITY CRISIS................ 4

a. Condensing Units Cost More Up-Front,

Thereby Increasing New Home Prices and

Reducing Housing Supply. ................................ 7

b. Increased Renovation Costs Reduce

Reinvestment in Existing Housing and Further

Worsen Housing Affordability ........................ 12

c. DOE’s Standards Narrow Consumer

Choice and Further Constrain Housing Access.

.................................................................. 14

II. THE D.C. CIRCUIT OPINION VIOLATES

LOPER BRIGHT ................................................ 16

iii

a. The D.C. Circuit improperly deferred to

DOE.................................................................. 17

b. Supreme Court review is warranted to

clarify how courts should handle statutes which

place a high burden of proof on nongovernmental entities. .................................... 19

CONCLUSION ..................................................... 20

iv

TABLE OF AUTHORITIES

Page(s)

Cases

Actavis Elizabeth LLC v. FDA, 625 F.3d 760 (D.C.

Cir. 2010)............................................................. 17

American Gas Ass’n, et al. v. U.S. Dept. of Energy,

et al., 157 F.4th 476 (D.C. Cir. 2025) ........... 17, 19

Loper Bright Enterprises v. Raimondo, 603 U.S. 369

(2024) ....................................................... 16, 17, 20

Federal Statutes

42 U.S.C. § 6313(a)(6)(B)(iii)(II)(aa) (2018) .......... 18

Other Authorities

Alex Lekov et al., Lawrence Berkeley Nat’l Lab.,

Economics of Condensing Gas Furnaces and

Water Heaters Potential in Residential Single

Family Homes (2010) ........................................ 8, 9

American Gas Association: Natural Gas Furnace

Efficiency Rule (2017) ........................................... 9

Bd. of Governors of the Fed. Rsrv. Sys., Report on

the Economic Well-Being of U.S. Households in

2024 (May 2025) ................................................... 7

Cal. Energy Comm’n, Affordable Near- and

Medium-Term Solutions for Integration of LowGWP Heat Pumps in Residential Buildings (June

2025) .................................................................... 10

v

Claire McKenna et al., Heating with Justice:

Barriers and Solutions to a Just Energy

Transition in Cold Climates, Resources,

Conservation & Recycling (May 31, 2024) ......... 10

Imani Moise, Americans With Higher Incomes Are

Starting to Fall Behind on Payments, Wall Street

J. (Feb. 12, 2026)................................................... 7

Joint Ctr. for Hous. Stud. of Harv. Univ., The State

of the Nation’s Housing 2025 (June 24, 2025) .......

................................................................... 5, 13, 14

Karen Bennett, Bankrate’s 2026 Annual Emergency

Savings Report (Feb. 4, 2026)............................... 7

Na Zhao, NAHB, Households Priced Out by Higher

House Prices and Interest Rates, NAHB.ORG (Feb.

2, 2026) .................................................................. 6

Na Zhao, NAHB, Nearly 75% of U.S. Households

Cannot Afford a Median-Priced New Home in

2025 (Feb. 2025).................................................... 5

Na Zhao, NAHB, The Age of the U.S. Housing

Stock, EYE ON HOUSING (Feb. 12, 2024) ............. 12

Nat’l Low Income Hous. Coal., The Gap: A Shortage

of Affordable Homes (Mar. 2024) ....................... 14

Natalia Siniavskaia, NAHB, The Size of the

Housing Shortage: 2021 Data, EYE ON HOUSING

(Dec. 16, 2022)................................................... 5, 6

Nat'l Multifamily Hous. Council & Nat'l Apartment

Ass'n, Comment on Energy Conservation

vi

Standards for Consumer Water Heaters, at 5–6

(Sept. 24, 2023) ................................................... 16

Paul Emrath & Caitlin Sugrue Walter, NAHB &

NMHC, Regulation: 40.6 Percent of the Cost of

Multifamily Development (June 2022) ................. 5

Paul Emrath, NAHB, Government Regulation in

the Price of a New Home: 2021 (May 5, 2021) ..... 5

R&R Heating and Cooling, Heat Pumps Ada, MI

https://rrmechanicalsvs.com/heat-pump-systemada-mi/ (last visited Feb. 13, 2026) .................... 11

Raphael Breit, Lowering the Heat Pump Cost

Barrier, Reg. Assistance Project (Jan. 9, 2025) . 11

Richard Valenzuela, Introduction to Residential

HVAC Level 1 (Dec. 23, 2025) ............................ 10

Rose Quint, NAHB, What Home Buyers Really

Want (March 2021) ............................................. 15

Travis Baugh, Carrier, 2026 Heat Pump Cost

Guide: Purchase, Installation & Repair (2026) . 11

U.S. Dep’t of Energy, Technical Support Document:

Energy Conservation Standards for Residential

Furnaces, app. 8D (Feb. 10, 2015).................... 8, 9

Regulations

Energy Conservation Program: Energy

Conservation Standards for Consumer Furnaces;

Final Rule, 88 Fed. Reg. 87,502 (Dec. 18, 2023) . 8,

12, 13, 14

1

INTEREST OF AMICI CURIAE 1

The National Association of Home Builders of the

United States (“NAHB”) is a Washington, D.C.based trade association whose mission is to enhance

the climate for housing and the building industry.

Chief among NAHB’s goals is providing and

expanding opportunities for all people to have safe,

decent, and affordable housing. Founded in 1942,

NAHB is a federation of more than 800 state and

local associations. About one-third of NAHB’s

approximately 140,000 members are home builders

or remodelers.

NAHB's Multifamily Council

represents the specific interests of builders,

developers, owners, and managers of all sizes and

types of condominiums and rental apartments.

NAHB is a vigilant advocate in the nation’s

courts. It frequently participates as a party litigant

and amicus curiae to safeguard the constitutional

and statutory rights and business interests of its

members and those similarly situated.

The National Association of REALTORS® is a

national trade association, representing 1.4 million

members, including its institutes, societies, and

councils involved in all aspects of the residential and

Counsel of record for all parties received notice at least

10 days prior to the due date of the amicus curiae’s intention to

file this brief. No counsel for a party authored this brief in

whole or in part, and no counsel or party made a monetary

contribution intended to fund the preparation or submission of

this brief. No person other than amici curiae, its members, or

its counsel made a monetary contribution to its preparation or

submission.

1

2

commercial real estate industries. Members are

residential and commercial brokers, salespeople,

property managers, appraisers, counselors, and

others engaged in the real estate industry. Members

belong to one or more of the approximately 1,200

local and 54 state and territory associations of

REALTORS®, and support private property rights,

including the right to own, use, and transfer real

property. REALTORS® adhere to a strict Code of

Ethics, setting them apart from other real estate

professionals for their commitment to ethical real

estate business practices.

3

SUMMARY OF ARGUMENT

Amid a national housing shortage and

affordability crisis, the United States Department of

Energy (“DOE”) implemented new energy efficiency

standards that increase the cost to construct a new

home and replace a major appliance in an existing

home. These standards will functionally remove

non-condensing water heaters and furnaces from the

market and replace them with condensing models,

which are more costly and often require extensive

renovation to fit into existing homes. DOE

promulgated these standards despite a restriction in

the Energy Policy and Conservation Act (“EPCA”)

not to promulgate energy efficiency standards if

interested parties prove that they would render a

product class which has certain “performance

characteristics” unavailable.

Factually, DOE’s standard will render noncondensing water heaters and furnaces unavailable.

Condensing water heaters and furnaces are more

expensive up front, and existing homes that

currently have non-condensing appliances will

require

expensive

modifications

to

install

condensing appliances which comply with DOE’s

new standards. Moreover, there is a strong

preference for non-condensing water heaters and

furnaces among homeowners and consumers.

Nonetheless, the D.C. Circuit found that the venting

mechanism, i.e. whether a water heater or furnace

is condensing or non-condensing, is not a

“performance characteristic” that consumers

consider when purchasing a water heater or furnace.

In rendering that decision, the D.C. Circuit

4

improperly deferred to DOE’s interpretation of

EPCA, in violation of this Court’s decision in Loper

Bright v. Raimondo.

This Court should grant a writ of certiorari to

correct the D.C. Circuit’s erroneous holding. DOE’s

energy efficiency standards impact housing

affordability nationwide, for both prospective and

existing homeowners and renters. Moreover, this

case presents an opportunity to reinforce Loper

Bright v. Raimondo, and would clarify how that case

impacts statutes like EPCA which impose burdens

of proof on the interested parties of the general

public.

ARGUMENT

I.

DOE APPLIANCE STANDARDS IMPOSE

COSTS THAT EXACERBATE AN ONGOING

HOUSING AFFORDABILITY CRISIS

The United States is experiencing a severe

housing shortage and an ongoing affordability crisis

that has left the housing market unable to absorb

additional cost burdens. Housing supply remains

historically constrained, vacancy rates are near

record lows, and a substantial majority of American

households are priced out of homeownership. Amid

these pressures, policies that raise the cost of

constructing, maintaining, or renovating homes

have outsized effects on housing affordability and

supply.

DOE’s appliance standards, promulgated under

EPCA, exacerbate these concerns. Across the

5

Nation, housing affordability has deteriorated

sharply. NAHB’s latest analysis finds that 74.9

percent of U.S. households are unable to afford a

new home at the median price of $459,826. Na Zhao,

NAHB, Nearly 75% of U.S. Households Cannot

Afford a Median-Priced New Home in 2025, at 1

(Feb. 2025). Moreover, industry data indicates that

government regulations across all levels account for

an average of 40.6 percent of multifamily

development costs. Paul Emrath & Caitlin Sugrue

Walter, NAHB & NMHC, Regulation: 40.6 Percent of

the Cost of Multifamily Development, 1 (June 2022).

Similarly, almost a quarter of the cost of a new,

single-family home is due to government

regulations. See Paul Emrath, NAHB, Government

Regulation in the Price of a New Home: 2021, at 1

(May 5, 2021) (regulation accounts for $93,870 of the

then-average price of a new home, $394,300).

Rising housing costs and elevated interest rates

have pushed home sales to their lowest level in

nearly three decades, directly limiting supply and

long-term access to homeownership. Joint Ctr. for

Hous. Stud. of Harv. Univ., The State of the Nation’s

Housing 2025, at 3 (June 24, 2025). NAHB data

shows that homeowner vacancy rates have fallen

below 0.9 percent, while rental vacancy rates have

declined to 5.2 percent—the lowest levels recorded

since the Census Bureau began tracking this data in

2005. Natalia Siniavskaia, NAHB, The Size of the

Housing Shortage: 2021 Data, EYE ON HOUSING

(Dec. 16, 2022).

The Nation does not have enough housing, with

economists estimating a deficit of at least 1.5 million

6

units. Id. At current building rates, that imbalance

is expected to persist for years as regulatory costs,

financing conditions, and supply-side constraints

continue to suppress new housing production. Id. In

such a constrained market, even modest increases in

construction or maintenance costs can materially

affect housing affordability and access.

In a housing market defined by limited supply,

cost increases do not operate at the margins. NAHB

analysis shows that relatively small increases in the

price of a new home are sufficient to price out large

numbers of households. Specifically, NAHB

estimates that each $1,000 increase in the median

price of a new home eliminates the ability of roughly

156,000 households to qualify for mortgage

financing, with first-time buyers and moderateincome families most affected. Na Zhao, NAHB,

Households Priced Out by Higher House Prices and

Interest Rates, NAHB.ORG (Feb. 2, 2026) 2. When

housing costs rise in an already constrained market,

fewer homes are built, fewer transactions occur, and

access to homeownership and rental housing is

further reduced.

Now is not the time to add more regulatory costs

to American households. In 2024, approximately

67% of American adults reported that they could pay

for an unexpected $400 expense using cash, savings,

or a credit card paid off at the next statement; the

remaining 33% reported paying for such an expense

2 https://www.nahb.org/news-and-economics/housing-

economics/housings-economic-impact/households-priced-outby-higher-house-prices-and-interest-rates

7

by borrowing money or selling personal belongings.

Bd. of Governors of the Fed. Rsrv. Sys., Report on the

Economic Well-Being of U.S. Households in 2024, at

41 (May 2025). However, according to a more recent

Bankrate survey, only 47% of Americans have

sufficient liquidity to cover a $1,000 emergency

expense. Karen Bennett, Bankrate’s 2026 Annual

Emergency Savings Report (Feb. 4, 2026).

Additionally, credit card and mortgage payment

delinquencies have increased significantly. In the

fourth quarter of 2025, U.S. household total debt

delinquency rose to 4.8 percent, the highest level

since 2017, and credit-card and auto loan

delinquencies are at their highest levels since the

2008 financial crisis. Imani Moise, Americans With

Higher Incomes Are Starting to Fall Behind on

Payments, Wall Street J. (Feb. 12, 2026). More

disturbing in the housing context is that 13 percent

of people with Federal Housing Administration

mortgages are not current on their loan payments.

Id. In short, average American households are less

able to absorb additional costs than DOE’s analysis

suggests.

a. Condensing Units Cost More Up-Front,

Thereby Increasing New Home Prices and

Reducing Housing Supply.

DOE’s appliance standards introduce significant,

unavoidable cost pressures into this already

constrained housing market. The Final Rule

requires residential gas furnaces manufactured

after December 18, 2028, to meet a minimum annual

fuel utilization efficiency of 95 percent. Energy

Conservation Program: Energy Conservation

8

Standards for Consumer Furnaces; Final Rule, 88

Fed. Reg. 87,502 (Dec. 18, 2023). DOE explained

that the standards are intended to improve energy

efficiency and reduce household energy consumption

by requiring the use of modern condensing

technology. Id.

Industry analysis indicates that traditional noncondensing gas furnaces are unable to meet this

efficiency threshold and will therefore no longer be

available once the standards take effect. As a result,

the standards establish minimum efficiency

thresholds for residential gas furnaces and certain

water heaters that can be met only by condensing

technology or electric alternatives.

Condensing gas furnaces generally carry

significantly higher upfront equipment costs than

traditional non-condensing models, and often

require additional installation work, including

specialized venting and condensate drainage

systems, which increases both labor and material

costs. U.S. Dep’t of Energy, Technical Support

Document: Energy Conservation Standards for

Residential Furnaces, app. 8D, at 8D-3 (Feb. 10,

2015). Condensing furnaces are more expensive to

manufacture because they require heavy-duty

hardware that standard models do not, including a

secondary heat exchanger to trap heat and

motorized power vents to manage exhaust. Alex

Lekov et al., Lawrence Berkeley Nat’l Lab.,

Economics of Condensing Gas Furnaces and Water

Heaters Potential in Residential Single Family

Homes, at 5 (2010).

9

This hardware requirement drives the average

consumer price of a condensing furnace in a new

home to $1,956, compared to just $1,481 for a

traditional model—a gap of nearly $500 per unit. Id.

Similarly, data from the American Gas Association

(AGA) indicates that, on average, condensing

furnaces cost about $350 more than non-condensing

furnaces, along with an additional $1,500 to $2,200

in installation costs. American Gas Association:

Natural Gas Furnace Efficiency Rule (2017). 3

The increased complexity of condensing

technology is a primary driver of these costs. Lekov

et al., supra, at 2. Unlike non-condensing units that

vent hot exhaust through standard metal chimneys

or B-vent systems, condensing units cool exhaust

until water vapor turns into liquid. U.S. Dep’t of

Energy, supra, at 8D-3. This process requires new

Category IV venting, typically polymer (PVC or

CPVC) routed horizontally through an exterior wall.

This switch from vertical metal venting to horizontal

plastic venting has been identified as the "main

difference in installation cost" between the two

technologies. Lekov et al., supra, at 5. This new

venting often necessitates wall penetrations and the

reconfiguration of mechanical spaces. U.S. Dep’t of

Energy, supra, at 8D-4.

Furthermore, because these units generate

significant liquid runoff, they require a dedicated

condensate drainage system. Richard Valenzuela,

Introduction to Residential HVAC Level 1, at 56

3 https://www.aga.org/wp-

content/uploads/2021/01/2017_furnace_efficiency_rule.pdf

10

(Dec. 23, 2025). This typically includes a specialized

trap and, in many installations, a condensate pump

to route the liquid to an appropriate disposal point.

Id. Because builders operate on thin margins, these

mandatory costs are passed directly to homebuyers,

making entry-level and moderately priced homes

more difficult to build and sell—further constraining

housing supply.

As a potential alternative, builders are

encouraged to install electric heat pumps. Id. at 32.

However, heat pumps are much more expensive to

buy and install. The primary reason homeowners do

not switch to heat pumps is their high cost. Cal.

Energy Comm’n, Affordable Near- and MediumTerm Solutions for Integration of Low-GWP Heat

Pumps in Residential Buildings 4 (June 2025).

Replacing an old gas furnace with a new heat pump

costs more than simply buying a new version of the

same gas furnace and air conditioner. Id. In

Michigan, shifting from natural gas heating to an

electric heat pump would raise the median

household energy burden 4 from about 6 percent of

income to 10 percent. Claire McKenna et al., Heating

with Justice: Barriers and Solutions to a Just Energy

Transition

in

Cold

Climates,

Resources,

Conservation & Recycling at 1 (May 31, 2024).

This price gap is consistent across the country.

While a new gas furnace and air conditioning combo

typically costs between $8,000 and $9,000, a

Energy burden is defined as a household’s energy

expenditures divided by household income. Here, even if the

appliance is more energy efficient, the cost of the energy used

is higher.

4

11

standard centrally ducted heat pump can range from

$10,000 to $12,000. Raphael Breit, Lowering the

Heat Pump Cost Barrier, Reg. Assistance Project

(Jan. 9, 2025). For homes requiring more complex

configurations, such as multi-zone ductless systems,

costs often climb to between $15,000 and $20,000.

Id. Beyond the equipment, professional installation

labor can vary significantly across the country.

Travis Baugh, Carrier, 2026 Heat Pump Cost Guide:

Purchase, Installation & Repair (2026). Even within

a location, labor costs can vary significantly

depending on a home’s size and insulation; one

provider in Michigan provides an estimate of $1,500

to $5,000 just for labor, with a total cost range of

$4,500 to $10,000. R&R Heating and Cooling, Heat

Pumps Ada, MI https://rrmechanicalsvs.com/heatpump-system-ada-mi/ (last visited Feb. 13, 2026).

Ultimately, DOE’s efficiency mandates are not

cost-neutral adjustments but significant structural

impediments to housing affordability. By effectively

banning traditional furnaces, the rule forces

builders to adopt technology that is inherently more

expensive to manufacture and more complex to

install. In a market where inventory is historically

low and prospective buyers are already stretched to

their financial limits, every additional dollar in

mandated construction costs pushes more

households out of the market.

12

b. Increased

Renovation

Costs

Reduce

Reinvestment in Existing Housing and

Further Worsen Housing Affordability

DOE’s appliance standards impose a severe and

disproportionate cost burden on the maintenance

and rehabilitation of the Nation’s existing housing

stock. America’s housing stock is aging; the median

age of an owner-occupied home is 40 years. Na Zhao,

NAHB, The Age of the U.S. Housing Stock, EYE ON

HOUSING (Feb. 12, 2024).Condensing furnaces were

introduced in the 1980s, when the median American

home was built, and efficiency standards at that

time did not require the new technology. For the

many homes that are older than 40 years,

condensing furnaces simply were not an option at

the time of construction. Yet these older houses

remain a critical and indispensable sector of the

housing market.

In millions of homes, non-condensing gas

furnaces and water heaters are integrated into the

dwelling’s physical structure, relying on established

vertical venting systems and specific spatial

configurations, such as closet spaces designed

specifically for the unit. Replacing non-condensing

appliances with compliant condensing alternatives

is rarely a simple swap; rather, it frequently

requires extensive structural and mechanical

modifications. These retrofits often necessitate

rerouting venting systems, opening finished walls,

installing condensate drainage infrastructure, and,

in some cases, relocating appliances entirely to

access an exterior wall. 88 Fed. Reg. at 87,537. These

retrofit requirements add substantial labor and

13

material costs that far exceed the price of the

appliance itself. DOE acknowledged this disparity,

stating that, in contrast to new construction, the

incremental retrofit installation cost for existing

homes is $539. Id. at 87,560.

This cost differential is driven by necessary

upgrades such as vent resizing, chimney relining,

the installation of new flue and combustion air

venting, and the resolution of complex venting

conflicts, such as "orphaned" water heaters that can

no longer share a chimney with the updated furnace.

Id. at 87,560–61. Additional financial burdens

include transportation, gas piping modifications,

ductwork, electrical hook-ups, and permit fees. Id. at

87,605. In multi-family settings, these projects must

also navigate rigid building code constraints that

make horizontal venting physically impossible in

certain interior units. Id. at 87,533–34. This comes

at a time when homeowners are increasingly costburdened, meaning they spend more than 30 percent

of their income on housing. Joint Ctr. for Hous. Stud.

of Harv. Univ., supra, at 26. Many homeowners

simply do not have the financial resources to afford

the costly renovations required to comply with the

Final Rule.

These escalated costs directly threaten housing

reinvestment and the preservation of supply.

Housing affordability depends not only on new

construction but also on the continuous

rehabilitation of existing units. Id. at 32–33. Across

the country, homebuilders and renovators routinely

acquire older or underutilized properties, modernize

them, and return them to the market. This process

14

is the primary mechanism for maintaining housing

supply in urban and infill markets where

developmental land is scarce. Id. at 1–2.

Yet rising materials and labor costs challenge the

ability of homebuilders to undertake renovation

projects. If the cost of a mandated retrofit exceeds a

project’s financial ceiling, the renovation does not

proceed, and the housing stock is left to deteriorate

or is removed from productive use entirely. 88 Fed.

Reg. at 87,602.

The resulting reduction in supply falls most

heavily on the Nation’s most vulnerable housing

markets. As renovation costs rise, fewer older homes

are rehabilitated, and a greater share of the housing

market becomes unsuitable for occupancy. This

inventory loss places immediate upward pressure on

both home prices and rents, specifically in

communities where housing shortages are already

most severe, such as the Los Angeles metro area,

South Florida, and the Northeast. Nat’l Low Income

Hous. Coal., The Gap: A Shortage of Affordable

Homes 18–22 (Mar. 2024). By increasing renovation

and retrofit costs, DOE’s appliance standards

effectively shrink the available housing supply and

exacerbate the very affordability crisis that federal

housing policy seeks to alleviate.

c. DOE’s Standards Narrow Consumer Choice

and Further Constrain Housing Access.

Finally, stringent DOE appliance standards

narrow consumer choice and stifle market

innovation by effectively removing widely used,

15

affordable technologies from the market and forcing

migration toward a single compliance pathway.

Builders, homebuyers, and homeowners value the

ability to choose appliances and energy systems that

align with their performance, affordability, and

household needs.

NAHB survey data confirm that a majority of

buyers prefer gas appliances; 51 percent of home

buyers prefer cooking with gas, while only 39

percent prefer electricity. Rose Quint, NAHB, What

Home Buyers Really Want (March 2021). By forcing

a single compliance pathway, the regulations

effectively disregard the clear preferences of these

consumers.

This requirement can slow or derail real estate

transactions. As stated, potential buyers have a

strong preference for gas appliances and, when due

diligence reveals that a non-condensing water

heater or furnace needs to be replaced with a

condensing unit, they are more likely to demand

concessions or price reductions, especially

considering the renovations many homes will

require to convert from non-condensing to

condensing units. Buyers may back out of sales if the

renovations required are extensive. This will add

new financial and logistical obstacles for home

buyers and REALTORS who are already working

through a stressed housing market.

Moreover, by mandating compliance with highefficiency standards, these regulations place gas

appliances out of reach for many buyers,

particularly in the affordable housing market. As a

16

result, builders are often forced to opt for electric

appliances not because they best meet the needs of

the home or its occupants, but because they are the

only

economically

feasible

option

during

construction. This forced migration towards a single

compliance pathway reduces energy choice and

raises long-term costs for residents. Nat'l

Multifamily Hous. Council & Nat'l Apartment Ass'n,

Comment on Energy Conservation Standards for

Consumer Water Heaters, at 5–6 (Sept. 24, 2023).

Given

the

financial

constraints

American

households currently face, many households may opt

to repair their gas appliances longer than they

would have simply because they can afford a repair

better than a new appliance, which keeps low

efficiency appliances functional longer. A standard

that improved efficiency but still allowed gas

appliances to operate would likely achieve

environmental goals faster, if only because it would

be more broadly adopted by consumers.

In a housing market already unable to meet

national demand, regulations that impose new,

unavoidable costs on the construction and

maintenance of homes directly worsen the housing

affordability crisis and may even undercut the

environmental goals they are trying to achieve.

II.

THE D.C. CIRCUIT OPINION VIOLATES

LOPER BRIGHT

Automatic agency deference ended with Loper

Bright Enterprises v. Raimondo, 603 U.S. 369

(2024). However, questions remain about how Loper

Bright applies to agency interpretations of the

17

statutes which govern them, as seen in the D.C.

Circuit’s decision in the instant case. Supreme Court

review is warranted to clarify what obligations, if

any, courts have to justify any deference they grant

to an agency. Supreme Court review is also

necessary to interpret how EPCA’s burden-shifting

framework works under Loper Bright.

a. The D.C. Circuit improperly deferred to DOE.

Under Loper Bright, “[c]ourts must exercise their

independent judgment in deciding whether an

agency has acted within its statutory authority, as

the APA requires. Careful attention to the judgment

of the Executive Branch may help inform that

inquiry. . . . But courts need not and under the APA

may not defer to an agency interpretation of the law

simply because a statute is ambiguous.” Id. at 412-13

(emphasis added). More expressly, the Court limited

the impact of how the Executive Branch could

influence decisions by saying “The views of the

Executive Branch could inform the judgment of the

Judiciary, but did not supersede it. . . . Otherwise,

judicial judgment would not be independent at all.”

Id.

The D.C. Circuit does not hide that it defers to

DOE. In fact, the Court states “We have no reason

to second-guess DOE’s view, especially since it rests

on the agency’s evaluations of scientific data within

its area of expertise.” American Gas Ass’n, et al. v.

U.S. Dept. of Energy, et al., 157 F.4th 476, 492-93

(D.C. Cir. 2025) (quoting Actavis Elizabeth LLC v.

FDA, 625 F.3d 760, 766 (D.C. Cir. 2010)) (internal

quotations omitted). Crucially, the Court here

18

expressly stated that it was going to accept DOE’s

interpretation unless given a reason not to do so,

which is improper under Loper Bright.

EPCA requires DOE to promulgate updated

efficiency standards, based on statutory factors, but

stipulates that DOE may not prescribe an efficiency

standard if “interested persons” establish “by a

preponderance of the evidence that [the standard] is

likely to result in the unavailability in the United

States in any product type (or class) of performance

characteristics (including reliability, features, sizes,

capacities, and volumes) that are substantially the

same as those generally available in the United

States.” 42 U.S.C. § 6313(a)(6)(B)(iii)(II)(aa) (2018).

Nobody contests that these new efficiency standards

will, as a factual matter, make non-condensing

furnaces and commercial water heaters unavailable.

The D.C. Circuit used this burden shifting

framework as an excuse to defer wholesale to DOE

without any independent evaluation of its own, as

required by Loper Bright. Instead of answering the

legal question presented, which was what

“performance characteristic” means, the Court

asked a factual question of whether appliances

which could meet the new efficiency standards may

be substituted for those which could not, then used

that finding to define “performance characteristic”

in the context of this case. It allowed one party’s

failure to carry its factual burden to determine a

phrase’s legal definition, which creates a loophole in

Loper Bright. The Court must close this loophole, or

it will render Loper Bright meaningless.

19

b. Supreme Court review is warranted to clarify

how courts should handle statutes which

place a high burden of proof on nongovernmental entities.

While federal agencies generally must prove that

their actions comply with federal statute, EPCA

essentially shifts the burden of proof to the general

public to show that a proposed standard would

render a class of appliances unavailable, and they

must prove unavailability by a preponderance of the

evidence. Here, Petitioners’ assertion that noncondensing water heaters and furnaces would

become unavailable was uncontested, and yet the

D.C. Circuit ruled “Petitioners failed to show, by a

preponderance of the evidence, that non-condensing

consumer furnaces and commercial water heaters

offer performance characteristics that are unlike

those offered by their condensing counterparts.”

American Gas Ass’n 157 F.4th at 493.

While Loper Bright requires courts to render

independent judgment, that mandate is less clear

when interpreting EPCA simply due to the burdenshifting language present in the statute. This

Court’s judgment is necessary to clarify how courts

should handle statutes like this one, where the

boundary between factual findings and legal

determinations is unclear. It is absurd to suggest

that a legal phrase, such as “performance

characteristic,” does not have a fixed meaning

within a statute, but instead relies upon what a nongovernmental entity can prove fits within that

phrase. That violates the premise of Loper Bright,

which is that statutes have a best reading. Loper

20

Bright, 603 U.S. at 400. Even if the result upon

review is the same, clarification is needed to help

lower courts better evaluate agency actions when

the factual and legal determinations overlap.

CONCLUSION

NAHB and NAR strongly urge this Court to

grant certiorari to close the loophole the D.C. Circuit

Court built into Loper Bright v. Raimondo, and to

review a finding by the D.C. Circuit upholding a

regulation which will exacerbate the ongoing

housing crisis.

Dated: February 23, 2026

Respectfully submitted,

Of Counsel:

JONATHAN WACLAWSKI

NATIONAL ASSOCIATION

OF REALTORS®

500 NEW JERSEY AVE, NW

WASHINGTON, D.C. 20001

(202) 383-1248

JWACLAWSKI@NAR.REALTOR

MACKENZIE PAYNE*

THOMAS J. WARD

SABREN WAHDAN

NATIONAL ASSOCIATION

OF HOME BUILDERS

OF THE U.S.

1201 15TH STREET, NW

WASHINGTON, D.C.

20005

(202) 266-8200

MPAYNE@NAHB.ORG

*Amici Curiae Counsel

of Record