What is Section 179D?

Section 179D is a federal tax incentive that rewards commercial building owners and designers for energy-efficient building improvements. It provides substantial tax deductions—up to $5.81 per square foot—for installing qualifying energy-efficient lighting, HVAC, and building envelope systems that reduce energy consumption compared to industry standards.

Significant Tax Savings

Claim up to $5.81 per square foot in immediate tax deductions, potentially saving hundreds of thousands of dollars on larger properties.

Accelerate ROI on Improvements

The tax deduction significantly improves the return on investment for energy upgrades, often shortening payback periods by years.

Enhanced Building Value

Energy-efficient improvements reduce operating costs and increase property marketability, creating both immediate tax benefits and long-term value.

179D Service

Who Can Claim the Deduction?

Commercial Building Owners

Tax-Exempt Building Owners

Architects & Engineers

Design-Build Contractors

Multi-Family Development (4+ Stories)

Government (Designers)

Religious, Charitable, and Tribal Organizations(Designers)

Warehouses

Office

Retail Properties

Manufacturing Properties

The 179D Process

Initial Assessment

CSSI reviews your building specifications and documentation to determine eligibility for deductions of up to $5.81 per square foot for energy-efficient commercial buildings.

Professional Site Visit

A CSSI licensed engineer conducts a comprehensive on-site inspection to document your building’s energy systems including HVAC, lighting, and building envelope.

Energy Modeling

Using IRS-approved software, our engineers model your building’s energy performance against ASHRAE standards to calculate your eligible deduction amount.

Certification & Filing

CSSI provides all required certification documentation and works with your tax professional to properly claim the deduction on your tax return

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Frequently Asked Questions

What is the 179D tax deduction?

The 179D tax deduction is an incentive for designing energy-efficient commercial buildings. Building owners can claim a tax deduction for installing qualifying energy-efficient systems.

What types of buildings qualify for the 179D deduction?

Qualifying buildings include commercial buildings and multi-family residential buildings four stories or higher. This includes offices, retail spaces, industrial buildings, warehouses, and apartment complexes.

What energy systems can qualify for the 179D deduction?

The deduction applies to three types of systems:

  • Interior lighting
  • Building envelope (roof, walls, windows, doors)
  • Heating, cooling, ventilation, and hot water systems
How much is the 179D deduction worth?

The deduction can be up to $5.81 per square foot for buildings that achieve a 50% reduction in energy costs compared to a reference building. Partial deductions of $0.60 per square foot are available for each qualifying system.

Who can claim the 179D deduction?
Who can claim the 179d deduction?

The deduction can be claimed by building owners, tenants, or designers of government-owned buildings.

Can the 179D deduction be claimed for retrofits or renovations?
Can the 179d deduction be claimed for retrofits or renovations?

Yes, the deduction can be claimed for both new construction and renovations of existing buildings.

What documentation is needed to claim the 179D deduction?
What documentation is needed to claim the 179D deduction?

You’ll need certification from a qualified individual (like a licensed engineer or contractor) that the required energy savings have been achieved. This typically involves energy modeling software to demonstrate the energy cost reductions.

How long has the 179D deduction been available?
How long has the 179d deduction been available?

The 179D deduction was first enacted in 2005 and has been extended and modified several times. It was made permanent in 2020 and expanded in 2022 under the Inflation Reduction Act.

 

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