Cost Segregation for Parking Garages: Why the IRS Says Most Are Buildings, Not Land Improvements

The Asset Everyone Gets Wrong

Ask most rental property investors what a parking garage depreciates as, and the instinct is to call it a land improvement, the same category as a driveway or a parking lot. That instinct is usually wrong, and it has real consequences. A surface parking lot recovers over 15 years as a land improvement. A parking garage, in most cases, recovers over 39 years as a nonresidential building. The difference in first-year deduction on a large structure can run into the hundreds of thousands of dollars, which is exactly why the IRS has taken an aggressive position on this issue and, in at least one case, assessed a negligence penalty against a taxpayer who classified a parking structure the wrong way.

If your property has a multifamily building, a hotel, a medical office, or a mixed-use development with an attached or freestanding parking structure, understanding how the IRS actually draws this line matters more than almost any other classification decision in your cost segregation study.

The Legal Line Between a Building and a Land Improvement

The recovery period for real property is governed by IRC Section 168 and the class life tables in Revenue Procedure 87-56. Nonresidential real property, defined as Section 1250 property that is not residential rental property, depreciates over 39 years. Land improvements, which include paving, curbing, sidewalks, and similar site work, depreciate over 15 years under asset class 00.3.

The question of what counts as a building is answered by Treasury Regulation Section 1.48-1(e)(1), which defines a building as any structure or edifice enclosing a space within its walls and usually covered by a roof, the purpose of which is, among other things, to provide shelter or housing, or to provide working, office, parking, display, or sales space. That regulation explicitly lists parking as one of the purposes that makes a structure a building. This single clause is the reason the IRS treats most parking structures as 39-year property rather than 15-year land improvements, even when the structure has open sides and no climate control.

The Case That Set the Standard: CCA 20125201F

The clearest statement of the IRS position came in Chief Counsel Advice Memorandum 20125201F. A taxpayer owned several stand-alone, open-air parking structures, multi-level structures with ramps connecting the levels, no enclosing walls, no elevators in some cases, and no heating or cooling. The taxpayer classified them as 15-year land improvements, reasoning that a structure with open sides, no floor-to-ceiling walls, and no conventional roof was really just a stack of parking lots rather than a building.

The IRS Chief Counsel's office rejected every argument. It held that Treasury Regulation Section 1.48-1(e)(1) does not require enclosing walls or climate control for a structure to qualify as a building. The regulation's own text lists parking as a building purpose, and the memo concluded that a structure built specifically to provide parking space, regardless of how open its sides are, meets the definition. The IRS went further and concluded that the taxpayer's position was not reasonably based on the law, applied a negligence penalty under Section 6662, and found that the taxpayer did not qualify for the reasonable cause and good faith exception. That combination, a technical loss plus a penalty, is what makes this memo required reading for anyone with a parking structure on their property.

This position is consistent with a 2009 IRS Coordinated Issue Paper on open-air parking structures, which reached the same conclusion using similar reasoning. Taken together, the guidance leaves very little room for an aggressive 15-year position on a genuine parking structure.

What Actually Distinguishes a Structure From a Lot

The practical test that emerges from this guidance turns on whether the asset is a stacked, multi-level structure designed to hold vehicles above grade, or a paved surface at grade level. A surface parking lot, even a large one serving a hundred cars, is unambiguously a 15-year land improvement. Curbing, striping, wheel stops, drainage systems, and the asphalt or concrete surface itself all qualify.

Once you introduce a second level, a ramp system connecting levels, and a structural frame that supports vehicle loads above grade, you have crossed into building territory under the IRS's reading of Section 1.48-1(e)(1), even if the structure has no exterior walls, no HVAC, and only minimal shelter from weather. The presence of stairwells, an elevator, interior lighting, or a fire suppression system reinforces the building classification but is not required to reach it. The controlling fact is the multi-level, structural nature of the asset and its purpose of providing parking space, not how enclosed it feels when you stand inside it.

There is one meaningful gray area the IRS memo itself acknowledges: a parking structure with no shared structural elements between levels, situated entirely underground, or with a genuine secondary function such as equipment storage, might support a different analysis. These fact patterns have not been fully tested, and an aggressive position here should only be taken with a documented engineering and legal analysis, not a generic template.

Why This Distinction Is Worth So Much Money

The dollar impact scales with the size of the structure. Consider a $22.7 million parking garage. Under the standard 39-year building schedule with no cost segregation, first-year depreciation on the structure alone is a modest fraction of the total basis, often well under 1%. When a proper cost segregation study is applied, not to reclassify the structural shell, but to separate out the site improvements, specialty electrical, signage, gate and access control systems, striping, and lighting that legitimately qualify for 15-year or 5-year treatment, the first-year depreciation can increase by several multiples. In one documented case involving a garage of this size, first-year depreciation rose from roughly $121,000 under straight-line treatment to over $1.1 million after a proper study, a tax savings of nearly $1 million from correctly identifying the components that were never part of the building shell in the first place.

The lesson is not that you should fight to call the whole structure a land improvement. Based on current IRS guidance, that fight is very likely to fail and could trigger a penalty. The lesson is that a large percentage of the value inside and around a parking structure genuinely is short-life property, and a properly engineered study captures that value without taking an indefensible position on the structural shell itself.

What Legitimately Qualifies for Shorter Recovery Inside a Parking Structure

Even after conceding that the structural frame, ramps, and floor slabs of a multi-level parking garage are 39-year property, a well-executed cost segregation study still identifies substantial value in components that are not part of the building shell. These typically include specialty and decorative lighting fixtures beyond basic code-required illumination, striping and traffic control markings, signage and wayfinding systems, gate arms, ticketing equipment, and access control hardware, security camera systems and their dedicated wiring, fencing and guardrails, landscaping and site drainage surrounding the structure, and exterior paving connecting the structure to adjacent surface lots or roadways.

For parking that is part of a larger building, such as a below-grade garage under an apartment building or an attached structure serving a hotel, the analysis becomes more complex because the parking levels need to be evaluated separately from the residential or hospitality space above, each governed by its own applicable recovery period and, for residential components, the 27.5-year schedule rather than 39 years.

Bonus Depreciation and Section 179 Limitations

Under the One Big Beautiful Bill Act, 100% bonus depreciation is now permanent for qualifying property with a MACRS recovery period of 20 years or less, placed in service after January 19, 2025. The components identified above, the 15-year land improvements and 5-year personal property inside and around a parking structure, are generally eligible for full first-year expensing under this rule. The structural shell of the garage itself, classified at 39 years, is not eligible for bonus depreciation because its recovery period exceeds the 20-year threshold in IRC Section 168(k)(2)(A)(i).

Section 179 expensing is generally unavailable for the parking structure itself because it is not Section 1245 personal property and does not qualify as qualified improvement property, a category limited to interior improvements of nonresidential buildings. Certain building systems within a parking structure, including fire protection and alarm systems and HVAC where present, can in some circumstances qualify for Section 179 treatment, though open-air structures typically lack these systems entirely.

Practical Guidance for Investors and Sponsors

If you own or are underwriting a property with a parking structure, whether a stand-alone garage, a below-grade structure under a multifamily building, or an attached deck serving a hotel or medical office, do not default to classifying the entire structure as a 15-year land improvement. That position is directly contrary to published IRS guidance and carries real audit and penalty risk if challenged. Instead, work with a cost segregation provider who understands the distinction between the structural shell and the site improvements, signage, security systems, and finish components that surround it, and who will document the engineering basis for each classification in a way that holds up under examination.

If you already have a parking structure on a property where a prior cost segregation study classified the entire structure as a land improvement, it is worth having that study reviewed. A defensible correction now, potentially through a change in accounting method on Form 3115, is far preferable to discovering the issue during an IRS examination years later, after interest and penalties have accrued.

The Bottom Line

Parking structures sit in a genuine gray zone of tax law, but the IRS has been clear about where it draws the line, and that line favors treating multi-level parking garages as 39-year buildings rather than 15-year land improvements. The real opportunity is not in relitigating that classification. It is in the careful, component-level work of identifying everything inside and around the structure that is not part of the building shell, from lighting and signage to access control and site drainage, and ensuring every one of those assets gets the shorter recovery period and, where eligible, full bonus depreciation that the law actually allows.

Stratum builds engineering-based, IRS audit-ready cost segregation studies that handle exactly this kind of nuance, including mixed-use properties with parking structures, in 14 business days. Get a free estimate today and see how much of your parking structure's value legitimately qualifies for accelerated depreciation.