Many of you may know, the One Big Beautiful Bill (OBBB) passed in July of 2025. What you may not be aware of is that the OBBB established an end date to the 45L Energy Efficient New Homes tax credit come June 30, 2026. This means all residential projects looking to take advantage of the $500-5,000 per home tax credit will have to be completed and acquired by June 30 of next year.
With this window quickly closing, Leyton has noticed an increase in concerns about timelines and nuances of program requirements related to 45L eligibility.
Our team has put together a list of frequently asked questions to help address some of the biggest concerns related to claiming 45L under OBBB for active projects.
Can I still claim 45L for projects completed in 2022?
Yes, if your residential project was completed and leased or sold in the year 2022, you may be eligible to claim the 45L tax credit retroactively.
This will only be applicable for the 2025 tax year, as the 45L tax credit allows for a 3-year lookback period. If you have residential properties that fit these criteria, we recommend reaching out to Leyton to review your project details.
What is required to claim?
Residential projects completed after January 1, 2023, need to be Energy Star Certified or DOE Energy Efficient Home (formerly known as Zero Energy Ready Homes) Certified to claim the 45L tax credit.
These programs are a design through construction process, where a credentialed Home Energy Rater guides the project team through the program requirements from design development all the way until final certificate of occupancy.
See Leyton’s webinar explaining the certification process below:
Is it too late for my project?
A pre-drywall inspection is a key milestone for projects pursuing Energy Star or DOE Energy Efficient Home Certification. This field inspection includes visually inspecting, measuring and grading the installation quality of insulation for the thermal envelope of the building.
If you have yet to insulate the building’s slab/floor, wall, and roof insulation, you may still have a chance if the project designs are in alignment with program requirements!
After completion of this inspection, a final test out of the units is required, including blower door tests, duct tests and ventilation flow rate testing.
How do I know if my project is a good fit for Energy Star or DOE Energy Efficient Home Certification?
Your project could be a fit for these programs if they meet key design requirements for Energy Star and DOE Energy Efficient Homes.
This includes meeting IECC 2009 (if multifamily) or IECC 2021 (if single family) insulation requirements in your specified IECC climate zone.
Your project could also be a gread fit if you utilize kitchen and bathroom exhaust fans and you design the building with proper air-tightness in mind.
Can projects be retroactively Energy Star certified?
Sadly, no. This is partly because the pre-drywall inspection is a hard requirement of the Energy Star and DOE Energy Efficient Home certification process.
This means that projects that would be looking to retroactively certify would have to remove drywall of potentially completed and/or occupied units. Adding significant labor costs to a project thought to be completed.
Additional testing would also need to be completed in each unit as well as documentation completed by other parties, such as mechanical design engineers or commissioning agents.
Our building will be complete, but not occupied by June 30, 2026, can we still claim 45L?”
Although your project may be Energy Star or DOE Energy Efficient Home certified by June 30, 2026, the one outstanding point made by the IRS is that the units are “acquired”, meaning leased or sold for residential use.
If I can’t claim the 45L credit, is it still worth certifying Energy Star or DOE Energy Efficient Homes?
Yes! If you are looking to increase the value of your project, while reducing energy consumption, certifying under Energy Star or DOE Energy Efficient Home programs is worth it.
There are plenty of incentives outside of federal tax incentives that benefit the builder, developers or homeowners. Depending on the state, town or city, you may be able to receive local incentives for building efficiently.
For example, utility providers in states like Massachusetts, California, Colorado, Texas, Connecticut and Michigan all offer different incentives for certifying new construction through Energy Star and DOE programs.
Larger multifamily projects can also reduce their mortgage insurance premiums through Commercial Property Assessed Clean Energy (CPACE) loans, by including Energy Star or DOE Energy Efficient Homes certification as an energy efficient bonus adder incentive.
As OBBB reshapes the landscape for energy efficiency incentives, 45L remains a powerful tool for those who act strategically.
Understanding how 45L interacts with OBBB can make the difference between losing money and optimizing your project’s performance.
To navigate these evolving rules with confidence and capture the maximum benefit available, contact Leyton’s experts today.
