179D Tax Deduction for Building Owners

The 179D deduction rewards building owners and designers for energy-efficient new construction and renovations. It applies to lighting, HVAC, and building envelope improvements that exceed ASHRAE 90.1 baselines.

To claim 179D, projects must be certified by a qualified professional who models energy performance against the applicable 90.1 standard. The deduction amount depends on the level of energy cost savings achieved.

A rigorous ASHRAE 211 audit with calibrated modeling and 90.1 baseline comparison provides much of the documentation needed to support a 179D claim.