As of August 2026: Section 179D, the energy-efficient commercial buildings deduction, is terminated for construction beginning after June 30, 2026; projects begun earlier remain claimable when placed in service. Qualifying projects required at least 25 percent modeled savings versus an ASHRAE 90.1 reference building, with 2026 deductions up to $5.94 per square foot.
The urgency hook has expired and CFOs will know — the winning angle is eligibility lock-in for pre-deadline projects. Eligibility turns on construction commencement (physical-work test or 5% safe harbor); pre-deadline projects remain claimable into 2027–2028. 2026 values: $0.59–$1.19/sf base, $2.97–$5.94 with prevailing wage/apprenticeship.
Tax-exempt owners may allocate the deduction to designers (Lancaster ISD: $1.8M eligibility). OBBBA 100% bonus depreciation survives as the live hook.
We advise before we quote. Tell us what you are working on and we will tell you whether this applies to your project.
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