Construction Incentive Programs: Energy, Historic, and Housing Credits

Construction incentive programs are federal, state, and utility offerings that lower the cost of building, renovating, or upgrading property through tax credits, tax deductions, specialized financing, and direct rebates. They target energy efficiency, historic preservation, affordable housing, and investment in distressed communities, and the biggest ones are administered through the tax code. Timing matters in 2026 because the One Big Beautiful Bill (P.L. 119-21), signed in July 2025, rewrote expiration dates and eligibility rules for several major energy incentives. Some doors are closing; others just widened.

Section 179D: Commercial Building Energy Deduction

Section 179D gives commercial building owners a tax deduction for installing energy-saving improvements to interior lighting, HVAC, or the building envelope. The project must cut the building’s total annual energy and power costs by at least 25 percent against an ASHRAE reference standard. For property placed in service before January 1, 2027, the benchmark is ASHRAE 90.1-2007; for property placed in service on or after that date where construction began on or after January 1, 2023, the benchmark shifts to 90.1-2019.¹

The deduction scales with savings. It starts at $0.50 per square foot at the 25 percent threshold and rises $0.02 per square foot for each additional percentage point of savings, capped at $1.00 per square foot at 50 percent. Meeting prevailing wage and registered apprenticeship (PWA) requirements multiplies the base amount by roughly five. The dollar amounts are indexed annually for inflation.¹

Prevailing Wage and Apprenticeship Rules

To qualify for the enhanced amount, all laborers and mechanics on the installation must be paid at least the prevailing wage rates set by the Department of Labor for the project’s area, and a required percentage of total labor hours must go to apprentices from registered programs. The requirements apply during installation, not to subsequent repairs.²

Designer Allocation on Government Buildings

Tax-exempt building owners such as federal, state, local, and tribal governments, plus nonprofits, churches, and schools, cannot use 179D themselves because they owe no income tax. They can instead allocate the deduction to the architect, engineer, contractor, or energy consultant who created the technical specifications. The allocation lives in a written agreement signed under penalty of perjury by the owner’s authorized representative, identifying the building, the cost of the qualifying property, and the allocated amount.³ That makes 179D one of the few federal tax incentives design professionals can claim directly for their work on public projects.

Section 45L: New Energy Efficient Home Credit

Builders of energy-efficient homes can claim a per-unit credit under Section 45L, but the window is closing. The One Big Beautiful Bill eliminated the credit for any home acquired after June 30, 2026. The first half of 2026 is the last chance.⁴

For a single-family home acquired before the deadline, meeting Energy Star Single-Family New Homes requirements produces a $2,500 credit, and certification under the Department of Energy’s Zero Energy Ready Home program produces $5,000.⁵ The home has to be sold or leased as a residence to qualify.⁶

Multifamily projects run on a different tier where prevailing wage compliance drives the amount. Without prevailing wage, Energy Star certification yields $500 per unit and Zero Energy Ready Home $1,000 per unit. With prevailing wage compliance, those amounts jump to $2,500 and $5,000 per unit.⁵ On a 200-unit project certified to Zero Energy Ready Home standards with prevailing wages, that is a $1 million credit.

Homeowner Energy Credits

Individual homeowners get their own credits, but the recent legislation reshaped them. The Residential Clean Energy Credit under Section 25D, which covered 30 percent of costs for solar, wind, geothermal, and battery storage, expired for expenditures made after December 31, 2025.⁷ Systems installed before that cutoff still qualify on 2025 returns, but new 2026 expenditures do not.

The Energy Efficient Home Improvement Credit under Section 25C covers 30 percent of certain upgrades subject to annual caps: $1,200 overall for items like insulation, windows (capped at $600), and exterior doors ($250 each, $500 total); a separate $2,000 cap for heat pumps and biomass stoves that stacks on top of the $1,200; and up to $150 for a home energy audit.⁸ The One Big Beautiful Bill also modified Section 25C, so confirm the current rules on the IRS site before committing to a 2026 project.⁹

Section 47: Historic Rehabilitation Tax Credit

Rehabilitating a certified historic structure earns a federal credit equal to 20 percent of qualified rehabilitation expenditures, spread evenly over five years starting the year the building is placed in service.¹⁰ On a $2 million rehab, that is $80,000 a year for five years.

A certified historic structure is a building either individually listed in the National Register of Historic Places or located in a registered historic district and certified by the Secretary of the Interior as historically significant to that district.¹⁰ The work itself also must be certified. The National Park Service evaluates the project against the Secretary of the Interior’s Standards for Rehabilitation, which require the work to preserve the building’s historic character.¹¹

Applications route through the State Historic Preservation Officer to the National Park Service. Each part is generally reviewed within 60 days. The NPS strongly encourages owners to secure approval before starting construction; beginning work first puts the certification at risk.

Section 48: Clean Energy Investment Tax Credit

Section 48 covers a broader set of energy property than 179D, including solar, fuel cells, geothermal, and energy storage. The base credit is 6 percent of the taxpayer’s basis in the energy property for projects with a maximum net output of 1 megawatt or greater (or where construction began on or after January 29, 2023). Meeting prevailing wage and apprenticeship requirements raises the rate to 30 percent.¹²

Bonus credits stack on top:

Energy communities: an additional 2 or 10 percentage points depending on project size and PWA compliance.
Domestic content: an additional 2 or 10 percentage points under the same structure.
Low-income communities and Indian land: an additional 10 percentage points; 20 percentage points if the project is part of an affordable housing development or benefits low-income households, but this bonus requires a separate allocation before the facility is placed in service.

Combined, the bonuses can push the effective credit to 50 percent or more of eligible costs.¹² Disposing of the property or losing qualifying status within five years of placed-in-service triggers partial recapture.¹³

Low-Income Housing Tax Credit

The Low-Income Housing Tax Credit (LIHTC) is the federal government’s main tool for affordable rental housing. Developers get credits that offset construction costs in exchange for reserving units at below-market rents for lower-income tenants, and the credits run over ten years.¹⁴

Two tiers exist. The 9 percent credit targets new construction and substantial rehabilitation not using certain other federal subsidies and was designed to deliver up to a 70 percent subsidy of eligible costs. The 4 percent credit applies to projects financed with tax-exempt bonds and was designed to deliver up to 30 percent. Both rates now have permanent statutory floors at their nominal percentages.¹⁴

State housing finance agencies allocate 9 percent credits under federally required qualified allocation plans, giving priority to projects serving the lowest-income households for the longest periods. In 2025, each state had $3.00 per capita in allocation authority. Starting in 2026, that authority permanently rises by 12 percent under the One Big Beautiful Bill. The 4 percent credit is paired automatically with qualified private activity bonds, and starting in 2026 developers qualify by financing at least 25 percent of a project with those bonds, down from the previous 50 percent.¹⁴ Because most developers sell the credits to institutional investors for upfront equity, LIHTC works less like a traditional tax break and more like federally subsidized financing.

New Markets Tax Credit

The New Markets Tax Credit attracts private investment into low-income communities. Investors receive a credit equal to 39 percent of the original investment, claimed over seven years, and the money must flow through a Community Development Entity certified by the Treasury Department’s CDFI Fund.¹⁵ It fits projects like manufacturing facilities, healthcare centers, and community buildings in distressed areas where conventional financing falls short.

PACE Financing

Property Assessed Clean Energy (PACE) financing lets commercial and, in some jurisdictions, residential property owners fund energy upgrades, water conservation, and resilience improvements through a voluntary assessment on the property tax bill. No upfront capital is needed; the owner repays over time through the assessment.¹⁶

The obligation attaches to the property, not the borrower. If the building sells, the buyer can assume the PACE payments along with the upgrades, though the buyer must agree to the transfer; if not, the seller may have to pay off the balance at closing.¹⁶ The catch is lien priority. A PACE assessment takes a senior position ahead of the mortgage, and that has made some mortgage lenders reluctant to approve loans on PACE-encumbered properties. It can also create friction when refinancing or selling. Understand the lien position before signing up.

Utility Rebate Programs

Local utilities run rebate programs offering direct payments for high-efficiency equipment: heat pumps, high-efficiency water heaters, insulation upgrades, LED lighting retrofits. Rebates come as a fixed dollar amount per piece of equipment or a percentage of purchase price.

Eligibility turns on technical specifications set by each utility and on where the property sits. One service territory might offer $400 for a qualifying water heater while another offers $1,000 for a heat pump. Funding pools are usually capped annually, so programs can close mid-year when the money runs out. Check your utility’s website or billing portal for open programs. Rules and timelines vary, but most rebates pay out within four to eight weeks of final approval.

Filing and Documentation

Underpreparing on paperwork is one of the fastest ways to lose a benefit you have earned. Missing documentation can lead to outright denial with no easy path to resubmit.

For Section 179D, taxpayers file IRS Form 7205 with the annual return. The form captures the qualifying property, the person performing the energy certification, and any allocation from a tax-exempt owner to the designer.¹⁷ Behind it sits a package of architectural specifications, energy modeling reports, and a qualified professional’s certification that the building meets the savings threshold against the applicable ASHRAE reference standard.¹

For Section 45L, the builder needs certification that the home meets Energy Star or Zero Energy Ready Home standards. The usual path is a Home Energy Rating System (HERS) assessment, where a certified rater inspects the home, gathers construction documents, and runs a simulation to produce a HERS Index score.⁶ For Section 47, the multi-part application goes to the National Park Service through the State Historic Preservation Officer, with detailed descriptions and photographs of the proposed work.¹⁸

Utility applications are simpler but exacting. Most want digital uploads of purchase receipts, contractor invoices, and equipment model numbers proving the installed product meets the efficiency tier. Some utilities conduct a desk audit or on-site inspection before releasing payment. Wrong model number or an invoice that fails to separate equipment from labor can stall payment.

Recapture Rules and Record Retention

Several incentives have strings that outlast the year you claim them. The Section 48 investment tax credit has a five-year recapture period. If you dispose of the property, change its use, or it stops qualifying within five years of placed-in-service, the IRS can claw back part of the credit.¹³ Projects that took the enhanced amount for PWA compliance face recapture if wage compliance lapses during the same five years. The recapture amount decreases by 20 percent for each full year the property stays in qualifying service, reaching zero after year five.

The historic rehabilitation credit carries its own five-year exposure. If a rehabilitated building stops being a qualified rehabilitated building during the allocation period, previously claimed amounts are subject to recapture.¹⁰

Keep documentation supporting any deduction or credit until the period of limitations for the return expires, generally three years from filing. For property-related deductions and credits, hold records until the limitations period expires for the year you dispose of the property, since those records support depreciation and gain-or-loss calculations on sale.¹⁹ Given the five-year recapture windows on the investment and rehabilitation credits, that means keeping energy certifications, HERS reports, NPS approval letters, and prevailing-wage payroll records well past the filing year.

1
Internal Revenue Service. Energy Efficient Commercial Buildings Deduction
2
Federal Register. Increased Amounts of Credit or Deduction for Satisfying Certain Prevailing Wage and Registered Apprenticeship Requirements
3
Internal Revenue Service. IRC 179D Energy Efficient Commercial Buildings Deduction
4
Internal Revenue Service. FAQs for Modification of Sections 25C, 25D, 25E, 30C, 30D, 45L, 45W, and 179D Under the One Big Beautiful Bill
5
Office of the Law Revision Counsel. 26 US Code 45L – New Energy Efficient Home Credit
6
Internal Revenue Service. Credit for Builders of New Energy-Efficient Homes
7
Office of the Law Revision Counsel. 26 USC 25D – Residential Clean Energy Credit
8
Office of the Law Revision Counsel. 26 USC 25C – Energy Efficient Home Improvement Credit
9
Internal Revenue Service. Energy Efficient Home Improvement Credit
10
Office of the Law Revision Counsel. 26 USC 47 – Rehabilitation Credit
11
National Park Service. The Secretary of the Interior’s Standards for Rehabilitation
12
Internal Revenue Service. Tax-Exempt Entities and the Investment Tax Credit
13
Internal Revenue Service. Instructions for Form 3468
14
Congressional Research Service. An Introduction to the Low-Income Housing Tax Credit
15
CDFI Fund. New Markets Tax Credit Program
16
US EPA. Commercial Property Assessed Clean Energy
17
Internal Revenue Service. Instructions for Form 7205
18
Internal Revenue Service. Rehabilitation Credit
19
Internal Revenue Service. How Long Should I Keep Records