Our expertise · Specialty Tax Incentives

Section 179D Studies

One deduction, four routes. Start with your role in the project.

Section 179D, the energy-efficient commercial buildings deduction, rewards efficient HVAC, lighting and building-envelope design — but who can claim it, and how, depends on your role. A taxable owner claims it on its own building. An architect or engineer can receive it by allocation from a public or tax-exempt owner. A Tribal Nation or public agency decides whether to make that allocation. Green Summit provides the engineering analysis, inspections and certifications behind every route, and our leadership has worked with 179D since 2007.

Licensed engineering firm
In-house CPAs
179D experience since 2007
Founded 2014
Audit-ready documentation

Who this is for: start with your role

Each route has its own eligibility rules, records and decision-makers. Pick the one that describes you and we will take it from there.

Building owners → Section 179D for Building Owners

You own a taxable commercial or multifamily building with qualifying HVAC, lighting or envelope improvements, and your tax team needs engineering-supported facts.

Designers → Section 179D for Designers

You are an architect, engineer or design-build contractor responsible for the technical specifications of qualifying systems on a government, nonprofit or Tribal building.

Tribal Nations → Designer Incentive & Allocation Support for Tribal Projects

Your Nation owns the building, pays no federal income tax, and is fielding allocation requests from designers.

Public & tax-exempt owners → Designer Allocation Support for Public & Tax-Exempt Owners

You are a school district, agency, university, hospital or nonprofit that needs a consistent way to review and document designer allocation requests.

What we do

Screen the project. Confirm ownership, construction-start and placed-in-service dates, the systems involved and which party can claim.
Evaluate the technical pathway. Identify the energy modeling, site inspection and certification the claim requires.
Coordinate the records. Bring owner, designer and advisor responsibilities into one clear workflow, including allocation letters where they apply.
Support the decision. Deliver the engineering package. The taxpayer and their advisors make the final filing decision — with evidence in hand.

What you receive

Eligibility screening, energy analysis, the required site inspection and a licensed engineer's certification, packaged as documentation your tax advisor can use. For designer routes, the executed allocation and its supporting records.

Why Green Summit

Green Summit is one of a select few firms nationwide that combine a licensed engineering firm with specialized tax expertise — so the team that models the building is the team that certifies it. Our leadership's 179D experience dates to 2007, before Green Summit was founded in 2014, and it shows in how we screen projects: property facts and dates first, deduction second. Every study we deliver is built to be audit-ready from day one: engineered substantiation, not estimates.

Frequently asked questions

What is Section 179D?

Section 179D is a federal deduction for energy-efficient commercial building property — qualifying interior lighting, HVAC and hot-water systems, and the building envelope — installed in commercial buildings, including qualifying multifamily buildings. Taxable owners claim it directly. For buildings owned by government, nonprofit and Tribal entities, the owner may allocate the deduction to the building's designer.

Who may benefit from a 179D study?

Eligible building owners, and eligible designers who receive an allocation from a specified tax-exempt owner, follow different routes. We begin with ownership, the installed property, the dates and the claimant's role before selecting the right scope.

Has 179D ended for every project?

No. The construction-start cutoff applies to property whose construction begins after June 30, 2026. Existing and transition projects require date-specific review; it is not a blanket completion deadline.

What does Green Summit deliver?

Eligibility screening, energy analysis, the required inspection and engineering certification, with documentation prepared for your tax advisor. Designer allocations also require the owner's separate authorization and supporting records, which we coordinate.

How long has your leadership worked with 179D?

Since 2007. That is professional experience, including work that predates Green Summit's founding in 2014, and it informs how we evaluate current eligibility and each claimant's records.

Is the deduction amount the same as cash received?

No. A deduction reduces taxable income under the applicable rules, so its value depends on the claimant's tax position. A designer allocation does not automatically create a payment to the building owner.

Let's talk about your project.

Tell us your role, the building and where it is, and when construction started or is expected to start.

Program and technical references

IRS: Energy Efficient Commercial Buildings Deduction

Program information reviewed September 22, 2026. Current applicability, qualifications and program terms are confirmed for each engagement.

Or call 321-273-2200 · inquiry@greensummit.com