Qualified Improvement Property (QIP) is a key tax depreciation concept for interior improvements to nonresidential buildings in the United States. When a business upgrades or replaces a furnace, the question is whether the cost can be treated as QIP. The answer depends on how the project is classified, what portion is considered interior and nonstructural, and when the property is placed in service. This article clarifies what qualifies as QIP, how depreciation works, and practical steps to determine if a furnace upgrade can be depreciated under QIP in current tax law.

What Is Qualified Improvement Property

Qualified Improvement Property refers to improvements to the interior of a nonresidential building that are placed in service after the building itself was placed in service. The key is interior, nonstructural work that enhances efficiency or usability without altering the building’s structural framework. The Internal Revenue Code excludes enlargements, elevators or escalators, and internal structural components from QIP. Examples include new interior walls, partition systems, ceilings, lighting, electrical wiring, plumbing modifications, and other nonstructural interior renovations. Importantly, QIP is defined by the improvement’s relationship to the interior space rather than by the type of asset installed. IRS Publication 946 and related IRS guidance provide the official framework for what qualifies as QIP.

Under the 2017 Tax Cuts and Jobs Act, qualified improvement property is eligible for favorable depreciation treatment. The recovery period for QIP was clarified to be 15 years, and property placed in service after 2017 may be eligible for 100% bonus depreciation in the year placed in service, with subsequent phase-downs beginning in 2023. This combination makes QIP a powerful tool for businesses making interior improvements, including certain HVAC modernization projects that qualify as interior, nonstructural improvements. For authoritative details, see IRS guidance on QIP and bonus depreciation rules.

How Is QIP Depreciated

Depreciation of QIP follows a modern framework designed to accelerate deductions for interior improvements. The main elements are:

Recovery period: Qualified Improvement Property generally uses a 15-year recovery period with straight-line depreciation.
Bonus depreciation: For property placed in service after September 27, 2017, and before 2023, 100% bonus depreciation was available, allowing businesses to deduct the full cost in the first year. Beginning in 2023, bonus depreciation begins to phase down (80% in 2023, 60% in 2025, 40% in 2025, 20% in 2026, and 0% in 2027 and later), unless extended or modified by future legislation.
Election and interaction with other rules: A business can elect out of bonus depreciation on a class-by-class basis, which affects the year one deduction and the remaining depreciable basis. The 15-year recovery period applies if bonus depreciation is not elected or is limited by taxable income, tax credits, or other limitations.
Qualified costs: The costs that qualify include materials and labor directly related to the interior improvement, as well as certain associated soft costs such as design, permits, and professional fees when they are part of the interior improvement project.

Taxpayers should consult a tax professional and reference IRS guidance, such as IRS Publication 946 and QIP-specific resources, to ensure the correct treatment for their particular project and year of service.

Does A Furnace Qualify As QIP

The central question is whether a furnace upgrade or replacement is an interior, nonstructural improvement that enhances the interior space rather than merely replacing a building’s mechanical equipment as a standalone asset. In practice, a furnace can qualify as QIP if the project is part of a broader interior renovation that changes the interior in a nonstructural way. Key considerations include:

Project scope: If the furnace replacement is part of an interior renovation (for example, upgrading the HVAC system as part of new interior finishes, lighting, and partitions), the related costs may be capitalized as QIP.
Structural components: Costs tied to structural changes or enlargements typically do not qualify as QIP. A pure replacement of a furnace that does not modify interior nonstructural components is less likely to be QIP.
Nonstructural improvements: If the furnace upgrade improves interior efficiency, comfort, or usability without altering the building’s structural framework, it is more likely to fit the QIP definition.
Placement in service date: The furnace-related costs must be placed in service after the building’s initial placement in service, consistent with QIP timing rules.
Documentation: The allocation between QIP and non-QIP costs matters. Thorough documentation is essential to support the classification in case of IRS review.

In many cases, a furnace replacement by itself may not be labeled as QIP. However, if it is part of an interior renovation that includes nonstructural improvements, the combined project may qualify. Because the line between building systems replacements and interior improvements can be nuanced, it is prudent to analyze the project with a tax professional who can review cost allocations and in-service dates for QIP treatment.

Practical Guidance For Furnace-Related Costs

Businesses contemplating a furnace upgrade or replacement should approach the project with a plan to maximize eligible depreciation while staying compliant. Consider the following steps:

Assess the project as an interior improvement: Determine whether the furnace work is part of a broader interior renovation that affects nonstructural interior components (walls, ceilings, lighting, cabling) rather than a purely mechanical upgrade.
Allocate costs properly: Separate interior improvements that qualify as QIP from stand-alone HVAC equipment costs that may be depreciated differently. Include labor, materials, permits, design, and related soft costs when they pertain to interior work.
Check placement and timing: Confirm that the interior improvement project is placed in service after the building’s initial occupancy. If some parts of the project precede the building’s opening, treat those costs according to their in-service dates.
Elect bonus depreciation if advantageous: If the QIP costs qualify and the business expects sufficient taxable income, 100% bonus depreciation in the first year can accelerate deductions. If not advantageous, the 15-year depreciation schedule may still be beneficial, especially with a steady year-over-year deduction.
Document the project: Maintain detailed invoices, contracts, project scopes, and cost breakdowns that show which elements are interior improvements and which are mechanical replacements. This documentation supports QIP classification if questioned by the IRS.
Coordinate with other tax provisions: Consider how QIP interacts with other depreciation provisions, repairs, and maintenance rules, as well as any state tax nuances that could affect your overall deduction.

For authoritative guidance, businesses should reference IRS materials on QIP and depreciation, and consider a consultation with a tax advisor who can tailor the treatment to the entity’s specific circumstances.

Common Scenarios And Pitfalls

Understanding common scenarios helps avoid misclassification and lost tax benefits. The following points summarize frequent pitfalls and how to handle them:

Repair versus improvement: A routine furnace replacement that simply restores the prior function without improving interior space is typically treated as a repair, not QIP, and is generally expensed or depreciated under standard repair rules. If the project adds interior improvements beyond restoration, QIP may apply.
Standalone HVAC equipment: Replacing only the furnace or other mechanical components without interior renovations may fall outside QIP. In such cases, depreciation is based on the asset class of the equipment (often with a shorter recovery period) and not the 15-year QIP period.
Mixed projects: When a renovation includes interior improvements and mechanical upgrades, allocate costs between QIP and non-QIP portions. The QIP portion benefits from the 15-year schedule and potential bonus depreciation.
In-service timing: Ensure the in-service date aligns with QIP rules. A delay in putting interior improvements into service can affect when depreciation begins and how bonus depreciation is applied.
Legislative changes: Depreciation rules for QIP and bonus depreciation can change with new tax law. Stay current on updates from the IRS and the U.S. Congress to optimize depreciation strategies.

In sum, a furnace upgrade can be considered QIP if it is part of a broader interior, nonstructural improvement project and is placed in service after the building’s initial use. When in doubt, consult a tax professional who can review project scope, cost allocation, and in-service dates to determine whether QIP treatment is appropriate.