Updating and Improving the Methodology for Assessing Affordability and Cost-Effectiveness of Building Energy Codes

Updating and Improving the Methodology for Assessing Affordability and Cost-Effectiveness of Building Energy Codes

DATES:

Meeting: DOE may hold stakeholder workshop(s) associated with this request for information. See section IV, "Public Participation," for registration information and participant instructions.

Comments: Written comments and information are requested by August 3, 2026.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Authority and Background

II. DOE Methodology for Evaluating Building Energy Codes Cost Savings

III. Issues on Which DOE Is Seeking Feedback

IV. Public Participation

V. Approval of the Office of the Secretary

I. Authority and Background

Section 307(b) of the Energy Conservation and Production Act (ECPA), as amended, directs DOE to periodically review the technical and economic basis of the voluntary building energy codes, and to participate in industry processes for their review and modification ( codified at 42 U.S.C. 6836(b)). DOE establishes robust technical methods and makes its analysis available to the public to ensure transparency to industry consensus bodies-the International Energy Conservation Code (IECC)  ⁽¹⁾ and ANSI/ASHRAE/IES Standard 90.1, ⁽²⁾ respectively-as well as states and local jurisdictions who are ultimately responsible for adopting and implementing building codes.

This request for information (RFI) seeks public input on DOE's methodology for assessing the consumer impacts of building energy codes, increasing transparency, and improving affordability of new construction. This notice is intended to solicit feedback on the overall methodology and on several specific questions outlined later in this document.

This RFI directly supports federal efforts to reduce regulatory burden and increase housing affordability for American homes and businesses. President Trump recently issued an Executive order aimed at making housing more affordable for Americans, stating, "[l]ayers of unnecessary regulatory barriers, slow permitting processes, and onerous mandates at all levels of government have delayed construction, restricted development, and driven up the costs of new housing." Executive Order 14394 of March 13, 2026, Removing Regulatory Barriers to Affordable Home Construction, 91 FR 13207 (Mar. 18, 2026). In addition, the U.S. Office of Management and Budget (OMB) recently issued an RFI seeking to identify ideas for deregulation across the U.S., including inviting comments on any regulations currently in effect. 90 FR 15481 (Apr. 11, 2025). As part of that OMB effort, stakeholders identified DOE's cost methodology and analysis as an opportunity to improve transparency and foster consumer affordability through building codes. ⁽³⁾

DOE has previously requested similar input on its methodology through related RFIs. See 78 FR 47677 (Aug. 6, 2013; 79 FR 27778 (May 15, 2014); and 80 FR 59757 (Oct. 2, 2015). Since establishing its methodology, DOE has continued to update it by collaborating with the IECC and Standard 90.1 technical committees, and by seeking continued input. DOE intends to continue to use its methodology to evaluate updated model building energy codes, particularly the IECC and Standard 90.1, as well as updated state and local building codes.

II. DOE Methodology for Evaluating Building Energy Codes Costs and Savings

This section provides an overview of DOE methodology and technical analysis. DOE defines residential buildings in a manner consistent with the IECC  ⁽⁴⁾ -one- and two-family dwellings, townhouses, and low-rise (three stories or less above grade) multifamily residential buildings-and, similarly, DOE defines commercial buildings in a manner consistent with both ASHRAE Standard 90.1  ⁽⁵⁾ and the commercial provisions of the IECC  ⁽⁶⁾ -buildings except one- and two-family dwellings, townhouses, and low-rise (three stories or less above grade) multifamily residential buildings. DOE's methodology centers on the perspective of American households and businesses. DOE relies on key metrics including:

• Incremental consumer costs ($)-net increase in initial capital costs associated with energy efficiency, such as equipment upgrades or additional energy efficiency measures ( e.g., wall insulation). ⁽⁷⁾

• Annual energy cost savings ($)-energy cost savings experienced by the consumer on an annual basis, such as through increased energy efficiency and an associated reduction in household utility bills.
• Payback period (years)-a straightforward calculation of incremental consumer costs divided by annual energy cost savings.

• Life-cycle cost analysis ($)-a more comprehensive accounting of net cost savings, typically over a 30-year period, ⁽⁸⁾ that considers energy savings and capital investments as financed through a typical mortgage. ⁽⁹⁾

DOE also conducts cash flow analysis that evaluates net annual cost outlays ( e.g., the difference between annual energy cost savings and increased annual costs for mortgage payments). This analysis helps identify years to positive cash flow, which is of primary interest to households and businesses as they consider energy efficiency upgrades and related capital investments.

DOE's approach to evaluating the net costs of energy efficiency measures involves discounting future savings and costs to a present value. This multistep process entails: (1) estimating the initial investments or incremental consumer costs of the changed provision(s);  ⁽¹⁰⁾ (2) estimating the energy savings of the changed code provision(s); and (3) calculating the corresponding economic impacts of the changed provision(s), including net consumer cost savings.

DOE's current methodology, as applied to residential and commercial building energy codes, is available for review at www.energycodes.gov/methodology. ⁽¹¹⁾

III. Issues on Which DOE Is Seeking Feedback

This section outlines several areas of opportunity and specific issues on which DOE is seeking input.

A. Issues Related to Estimating Costs of Code Updates

1. Costs to Consumers

DOE is seeking input to ensure consumer costs are accurately reflected in analysis. Historically, to estimate incremental costs, DOE has relied on prominent and publicly available sources like RS Means, ⁽¹²⁾ online catalogues, retail home improvement stores, journal articles, ENERGY STAR® cost summaries, and published research studies, as well as data produced by professional cost estimating firms. DOE considers different aspects when estimating these costs, including unit measurement, quantity, material cost, labor cost, overhead and profit, additional engineering and design, and additional considerations for unique measures, such as building and systems commissioning. However, obtaining costs from disparate sources can lead to inconsistencies. For instance, some sources may more closely reflect a wholesale cost to a builder rather than the final cost paid by the consumer. DOE is seeking suggestions for cost data and other considerations to more accurately reflect the real market costs paid by consumers (Topic Q01).

2. Cost Database

While DOE develops its own cost estimates, industry stakeholders and code development committees typically are limited to publicly available data to develop cost estimates for potential code changes. No centralized cost estimate database for code measures currently exists; however, such a resource could potentially help increase transparency of cost data sources, streamline cost analyses throughout the industry, and ultimately lead to data that is more reflective of the costs paid by consumers. DOE has previously received feedback that such a database would benefit the industry and would better capture and create uniformity around building energy efficiency expenditures faced by households and businesses. DOE is seeking feedback on the need for a publicly available database that estimates real market costs to consumers from building energy code measures (Topic Q02).

3. Regional Differences

Regional differences, such as builder construction practices and weather conditions, can also create a barrier to developing incremental cost data that applies to the entire country. For instance, certain materials that may be common and comparatively cheap in the Midwest may be rarely used or require additional transportation expenses in the Southeast. Further, labor markets differ across the U.S., particularly in terms of construction volume and access to skilled labor, which has a significant impact on construction cost. DOE is seeking feedback on how to better consider and incorporate regional differences when evaluating real market costs to consumers, and suggestions for data that demonstrate those regional differences (Topic Q03).

B. Issues Related to Estimating Energy Savings of Code Updates

1. Economic Benefits to Consumers

Estimating energy savings associated with energy efficiency measures typically requires the use of energy modeling simulation software. This approach is also used when evaluating a combination of energy measures, such as an entire code update, because the measures may have interactive effects ( e.g., increased insulation and more efficient lighting reduce heating loads which may reduce overall HVAC system size). However, there are some instances where it is not possible to model a measure, typically when it is either not a technology or material that has been added to the modeling software or if the measure does not provide direct energy efficiency cost savings but, rather, other benefits, such as energy demand cost savings. In addition, stakeholders commonly express the desire to evaluate additional benefits to consumers, such as increased durability, comfort, productivity, and disaster resistance, and building code requirements are often proposed upon an assumption of such benefits. However, standardized and uniform methods for evaluating such impacts-and quantifying related consumer costs-are not well established or accepted across the industry. DOE is seeking suggestions for data and analysis approaches that more accurately reflect economic benefits to consumers (Topic Q04).

2. Utility Costs and Energy Metrics

When evaluating building codes or individual measures at the national level, industry and technical committees typically attempt to identify costs that most closely represent the average cost paid by consumers across the country or a given region. Historically, for national-level analyses DOE used average blended energy costs that are based on the most recent full-year, publicly available data from the U.S. Energy Information Administration (EIA), whereas state-level analysis uses state-specific average blended energy costs from the most recent full-year data from EIA. While state-specific analyses can more closely reflect regional variability in utility costs, the national-level analyses do not capture this variation, which could lead to an overgeneralization of energy cost savings since utility costs vary dramatically across the country. DOE is considering evaluating additional metrics beyond energy costs, site energy, and source energy, and plans to add full fuel cycle energy. Additionally, DOE is particularly interested in better reflecting consumer costs for single-family homes and plans to more clearly delineate impacts between single-family and multifamily buildings in its analysis. DOE is seeking suggestions for data and metrics that could more accurately reflect energy costs to consumers and the appropriateness of considering regional differences in energy costs (Topic Q05).

3. Prototype Models

DOE develops a set of prototype building models that are used to assess the energy- and cost-savings from residential and commercial codes and code changes. These prototype models are intended to be representative of the U.S. building stock across all U.S. regions based on data from the U.S. Census Bureau. The single-family home prototype is a two-story 2,376 ft ² building based on recent average home size for single-family construction. DOE maintains a similar prototype for multifamily construction and is considering adding additional options to its suite of residential prototypes, such as a smaller single-family home that could help better represent the range of housing options. Commercial prototypes encompass a larger variety of buildings-from small, medium, and large offices to outpatient healthcare to non-refrigerated warehouses-that cover approximately 75 percent of new construction commercial building floor area in the United States. Given the plan to rapidly expand data center construction in the U.S., ⁽¹³⁾ DOE is considering adding a data center prototype, as well as other commercial building types that could aid the industry in evaluating construction costs. DOE is seeking suggestions for adding new or reconfiguring existing prototype buildings to better evaluate affordability and reflect the makeup of the residential and commercial buildings market (Topic Q06).

C. Changes and Issues Related to Estimating Affordability of Code Changes

1. Affordability Metrics

Consumer costs are a primary consideration for DOE to improve analyses on consumer affordability, choice, and purchasing power. Metrics could focus on upfront affordability, ongoing monthly affordability, long-term affordability, affordability relative to changing residential energy costs, and the ability to make use of abundant available energy sources while safeguarding consumer choice. For example, expanded analysis could include affordability impacts on first-time homeowners, new businesses, and average household economics, or the effect of energy price and utility bill volatility on consumer affordability. Similar metrics could be applied to commercial buildings to evaluate affordability for business owners. DOE is seeking feedback on the appropriateness of considering additional metrics that better demonstrate expanded impacts on consumer affordability, consumer choice, and purchasing power (Topic Q07).

2. Cost-Effectiveness Approach

The industry technical committees that develop building energy codes rely upon a number of different approaches and metrics for calculating consumer costs and evaluating affordability impacts. For instance, some approaches for evaluating proposed code updates are based on a simple payback period, or establish a payback threshold ( e.g., 5-year payback). The ASHRAE Standard 90.1 technical committee uses the "scalar ratio" method, ⁽¹⁴⁾ which is a ratio of savings to investment and is typically applied to commercial investment scenarios. Life-cycle cost analysis (LCCA) considers the time value of money and includes a discount rate ( i.e., discounts the value of future energy cost savings). Federal cost-analysis principles specify a life-cycle costing method, outlined in OMB Circular A-94, which accounts for incremental costs and savings and present values, and discounts the value of future savings. DOE's cost analyses have historically included all the methods listed above and, in addition to discount rate, DOE's approach factors in parameters such as energy price escalation rates, income tax, and mortgage rates, among others. DOE is seeking input on appropriate discount rates and payback periods, including potential thresholds for payback periods. While DOE favors including all the calculations above to remain responsive to the full range of federal, state, and local laws and requirements, the Department seeks feedback on this topic and the potential for new approaches (Topic Q08).

3. Evaluation Period

Individual code change proposals are typically evaluated according to their expected measure-life, or how long they are expected to last before needing to be replaced, and based on the costs and benefits to the consumer. For commercial buildings, ASHRAE 90.1's Scalar Ratio method considers equipment like rooftop air conditioners on an 18-year time horizon, ⁽¹⁵⁾ whereas building envelope upgrades like insulation or windows are more likely to be viewed on a 30- or 40-year time horizon based on the accepted longevity of the respective measures. When conducting life-cycle cost assessments of residential building energy codes, DOE has traditionally evaluated the economic impact over 30 years, which matches the perspective of a typical home buyer, and allows for an understanding of cashflows over a traditional 30-year mortgage. Similarly, DOE evaluates the economic impact of commercial buildings over 30 years, which is consistent with recommendations and data from the National Institute of Science and Technology (NIST) and OMB. Note that these 30-year timeframes represent the overall period of analysis (or "study period"), with individual measures purchased, amortized, and often replaced within that period, with residual values, as applicable (as opposed to a 30-year payback period). However, DOE also recognizes that homeowners often make investment decisions on shorter timeframes, and that typical homeowners own their home for an average of 12 years, although tenures vary widely across the U.S. ⁽¹⁶⁾ DOE is seeking suggestions for data and studies that demonstrate the appropriate length of time that is applicable to energy efficiency measures, and better methods of evaluating benefits to consumers (Topic Q09).

D. Broader Issues Affecting Consumer Costs and Regulatory Burden

1. Transparency in Industry Consensus Processes

Industry consensus-based processes for reviewing and updating building energy codes, including the IECC and Standard 90.1, are open to the public and any party may participate and submit code change proposals. However, in practice, processes to develop building codes and standards are technical and time-intensive in nature, requiring a level of effort beyond what would be reasonable for a typical consumer or interested member of the public. In addition, codes and standards development processes have certain restrictions regarding copyrights, proprietary data, competition, and access to information that can be prohibitive to consumer representation. Stakeholders have also expressed concerns related to procedure, committee composition, and access to transparent data and technical information surrounding the development of building energy codes. DOE is seeking feedback regarding how to enable greater data transparency and consumer representation within building energy code review and consensus processes. DOE is interested in approaches such as consumer-oriented surveys, consumer participation in code development processes, and working groups or similar efforts that can better identify and represent consumer interests and needs and that can help better inform building energy code review and update processes. In addition, DOE is seeking feedback on potential alternatives to the IECC and Standard 90.1 that can better represent consumer interests and better meet the objectives of safeguarding affordability and consumer choice (Topic Q10).

2. Permitting Delays and Localized Regulatory Costs

Consumers and industry stakeholders are faced with a wide range of costs associated with building construction regulations beyond meeting the minimum requirements imposed by building energy codes. Many municipalities exhibit long permitting and approval timelines that lead to excessive delays that increase costs and are ultimately paid for by the consumer. Some jurisdictions have implemented dashboards or other approaches to increase transparency about these delays and costs. Builders and developers also face constraints that further increase consumer cost and inhibit the widespread affordability and availability of housing ( e.g., local zoning and land use requirements, and impact fees). DOE is interested in feedback on the broader regulatory issues that impede building construction and increase costs and potential solutions. (Topic Q11).

3. Cost Drivers of New Construction

DOE is interested in feedback on broader drivers of increased cost in new building construction. These include the "hard costs" of construction, labor costs, land availability, as well as housing supply and other drivers. DOE is interested in data sources, including with regional specificity, building types, or building sizes, that can inform future analysis of the "baseline" costs of new construction, and what portions of those costs can be directly attributable to materials, equipment, and labor, as well as factors such as financing models or other contributors to the purchase price of new homes and commercial buildings. DOE is also seeking input on opportunities to lower costs through innovative construction methods, both onsite and offsite methods such as industrialized construction ( e.g., prefabricated or modular housing solutions). DOE also seeks information and data on any additional cost drivers, including those not explicitly mentioned here, that have the potential to significantly reduce construction costs and that commenters believe DOE should consider when assessing new construction affordability (Topic Q12).

In addition to the topics outlined above, DOE requests feedback on broader issues pertaining to its methodology and related technical analysis for residential and commercial buildings.

E. Summary of Issues on Which DOE Seeks Information

Q01. Suggestions for cost data and other considerations that more accurately reflect the real market costs paid by consumers.

Q02. The appropriateness of developing and maintaining a publicly available database that estimates real market costs to consumers from building energy codes.

Q03. The appropriateness of considering regional differences when evaluating real market costs to consumers and suggestions for data that demonstrate regional differences.

Q04. Suggestions for data and analysis approaches that more accurately reflect economic benefits to consumers.

Q05. Suggestions for data and metrics on energy costs that more accurately reflect costs paid by the consumer and the appropriateness of considering regional differences in energy costs for national-level analyses.

Q06. Suggestions for adding new or reconfiguring existing prototype buildings to better evaluate affordability and reflect the makeup of the housing and buildings market.

Q07. The appropriateness of considering additional metrics that better demonstrate expanded impacts on consumer affordability, consumer choice, and purchasing power.

Q08. Input on appropriate discount rates and potential thresholds for payback periods and suggestions for updating existing cost analysis approaches or utilizing new approaches.

Q09. Suggestions for data and studies that demonstrate the appropriate length of time that is applicable to energy efficiency measures, and better methods of evaluating benefits to consumers.

Q10. Feedback on transparency and consumer representation in code development processes.

Q11. Input on broader issues of regulatory burden caused by permitting delays and localized regulatory costs.

Q12. Suggestions for drivers and data sources for broader costs of new construction for residential and commercial buildings.

IV. Public Participation

A. Stakeholder Workshop

DOE may hold a stakeholder workshop associated with this request for information. The workshop would be open to any interested participant and occur during the public comment period (See public comment deadline in the DATES section of this document). DOE would use the workshop to seek additional public participation and feedback, in addition to written comments, and to allow for a more iterative discussion of the pertinent issues and questions. More information on the stakeholder workshop, including registration information and participant instructions, would be available at: www.energycodes.gov.

B. Submission of Comments

DOE invites all interested parties to submit in writing by the date listed in DATES section of this document, comments and information on matters addressed in this notice and on other matters relevant to DOE's methodology and related technical analysis for residential and commercial building energy codes.

Submitting comments via www.regulations.gov. The www.regulations.gov web page will require you to provide your name and contact information. Your contact information will not be publicly viewable except for your first and last names, organization name (if any), and submitter representative name (if any). If your comment is not processed properly because of technical difficulties, DOE will use this information to contact you. If DOE cannot read your comment due to technical difficulties and cannot contact you for clarification, DOE may not be able to consider your comment.

However, your contact information will be publicly viewable if you include it in the comment or in any documents attached to your comment. Any information that you do not want to be publicly viewable should not be included in your comment, nor in any document attached to your comment. If this instruction is followed, persons viewing comments will see only first and last names, organization names, correspondence containing comments, and any documents submitted with the comments.

Do not submit to www.regulations.gov information for which disclosure is restricted by statute, such as trade secrets and commercial or financial information (hereinafter referred to as Confidential Business Information (CBI)). Comments submitted through www.regulations.gov cannot be claimed as CBI. Comments received through the website will waive any CBI claims for the information submitted. For information on submitting CBI, see the Confidential Business Information section.

DOE processes submissions made through www.regulations.gov before posting. Normally, comments will be posted within a few days of being submitted. However, if large volumes of comments are being processed simultaneously, your comment may not be viewable for up to several weeks. Please keep the comment tracking number that www.regulations.gov provides after you have successfully uploaded your comment.

Submitting comments via email, hand delivery, or postal mail. Comments and documents submitted via email, hand delivery, or mail also will be posted to www.regulations.gov. If you do not want your personal contact information to be publicly viewable, do not include it in your comments or any accompanying documents. Instead, provide your contact information on a cover letter. Include your first and last names, email address, telephone number, and optional mailing address. The cover letter will not be publicly viewable as long as it does not include any comments.

Include contact information each time you submit comments, data, documents, and other information to DOE. If you submit via mail or hand delivery, please provide all items on a CD, if feasible. It is not necessary to submit printed copies. No facsimiles (faxes) will be accepted.

Comments, data, and other information submitted to DOE electronically should be provided in PDF (preferred), Microsoft Word or Excel, WordPerfect, or text (ASCII) file format. Provide documents that are not secured, written in English, and free of any defects or viruses. Documents should not contain special characters or any form of encryption and, if possible, they should carry the electronic signature of the author.

Campaign form letters. Please submit campaign form letters by the originating organization in batches of between 50 to 500 form letters per PDF or as one form letter with a list of supporters' names compiled into one or more PDFs. This reduces comment processing and posting time.

Confidential business information. Pursuant to 10 CFR 1004.11, any person submitting information that he or she believes to be confidential and exempt by law from public disclosure should submit via email, postal mail, or hand delivery two well-marked copies: One copy of the document marked confidential including all the information believed to be confidential, and one copy of the document marked "non-confidential" with the information believed to be confidential deleted. Submit these documents via email or on a CD, if feasible. DOE will make its own determination about the confidential status of the information and treat it according to its determination.

It is DOE's policy that all comments may be included in the public docket, without change and as received, including any personal information provided in the comments (except information deemed to be exempt from public disclosure).

V. Approval of the Office of the Secretary

The Secretary of Energy has approved publication of the request for information.

Signing Authority

This document of the Department of Energy was signed on April 28, 2026, by Audrey Robertson, Assistant Secretary (EERE) for Critical Minerals and Energy Innovation, U.S. Department of Energy, pursuant to delegated authority from the Secretary of Energy. That document with the original signature and date is maintained by DOE. For administrative purposes only, and in compliance with requirements of the Office of the Federal Register, the undersigned DOE Federal Register Liaison Officer has been authorized to sign and submit the document in electronic format for publication, as an official document of the Department of Energy. This administrative process in no way alters the legal effect of this document upon publication in the Federal Register .

[FR Doc. 2026-08646 Filed 5-1-26; 8:45 am]

BILLING CODE 6450-01-P

⁽¹⁾  As administered by the International Code Council (ICC).

⁽²⁾  As administered by the American Society for Heating, Refrigerating and Air-conditioning Engineers (ASHRAE) in cooperation with the American National Standards Institute (ANSI) and Illuminating Engineering Society (IES).

⁽³⁾  See https://www.regulations.gov/document/OMB-2025-0003-0001.

⁽⁴⁾  International Code Council. 2024 International Energy Conservation Code (IECC). Available at: https://codes.iccsafe.org/content/IECC2024P1/index.

⁽⁵⁾  American Society of Heating, Refrigerating and Air-Conditioning Engineers. ANSI/ASHRAE/IES Standard 90.1-2022: Energy Standard for Buildings Except Low-Rise Residential Buildings. Available at: https://www.ashrae.org/technical-resources/bookstore/standard-90-1.

⁽⁶⁾  International Code Council. 2024 International Energy Conservation Code (IECC). Available at: https://codes.iccsafe.org/content/IECC2024P1/index.

⁽⁷⁾  Incremental consumer costs are also often referenced as "first costs" or "upfront costs."

⁽⁸⁾  Commensurate with the typical homeowner mortgage period.

⁽⁹⁾  Life-cycle cost analysis provides a more comprehensive accounting of costs experienced by the consumer, such as increased mortgage costs, tax impacts, residual values, maintenance and replacement costs, and other parameters.

⁽¹⁰⁾  Often referenced as the "upfront costs" or "first costs."

⁽¹¹⁾ See https://www.energycodes.gov/sites/default/files/2024-10/residential_methodology_2024.pdf for residential buildings and https://www.energycodes.gov/sites/default/files/2024-10/Commercial_Cost_Effective_Method_2024.pdf for commercial buildings.

⁽¹²⁾  RS Means is a prominently relied upon source of cost data containing traditional estimates of material, labor, and equipment costs, plus regional adjustment factors accounting for volatility of pricing in markets across the U.S.

⁽¹³⁾ See "Winning the Race, America's AI Action Plan (July 2025); available at https://www.whitehouse.gov/wp-content/uploads/2025/07/Americas-AI-Action-Plan.pdf.

⁽¹⁴⁾  McBride, Development of Economic Scalar Ratios for ASHRAE Standards 90.1 (year), available at https://consensus.fsu.edu/FBC/2010-Florida-Energy-Code/901_Scalar_Ratio_Development.pdf.

⁽¹⁵⁾  Sample ASHRAE Equipment Life Expectancy Chart, available at https://www.naturalhandyman.com/iip/infhvac/ASHRAE_Chart_HVAC_Life_Expectancy.pdf.

⁽¹⁶⁾  Press Release, Redfin, The Typical U.S. Homeowner Hangs Onto Their House for 12 Years. In Los Angeles, It's 20 Years (Mar. 6, 2026), available at https://www.redfin.com/news/press-releases/the-typical-u-s-homeowner-hangs-onto-their-house-for-12-years-in-los-angeles-its-20-years/.