Consider a hypothetical owner of a seven-bay repair shop who has just spent nearly $900,000 expanding the facility: three new lifts, an oil-water separator to meet updated city code, dedicated electrical and compressed-air lines for the new equipment, and repaved drive lanes for heavy truck traffic. The owner assumes all of it will be depreciated over 39 years because “that’s just how commercial property works.”

The lifts are equipment and are depreciated on their own schedule. For the rest, a cost segregation study would separate the components that carry shorter tax lives, such as the equipment connections and site work, from the 39-year building. With bonus depreciation, those components could be deducted in the first year instead of over decades.

Many auto repair shop owners are in the same position: they invest in specialized infrastructure and depreciate most of it on the default 39-year schedule. Cost segregation addresses that.

The Core Idea Behind Cost Segregation

At its core, cost segregation is about recognizing that not every part of a building wears out on the same timeline. The IRS treats a shop as one 39-year asset by default, but the reinforced concrete under a two-post lift doesn’t have the same lifespan as the shingles on the roof. Neither does the dedicated electrical line running your compressor.

An engineering-based cost segregation study breaks your property down into these distinct components and assigns them to their appropriate tax lives. Auto repair falls under IRS asset class 57.0, where most personal property is 5-year. For auto repair shops, that typically means:

• 5-year property (dedicated electrical, air and exhaust systems serving shop equipment, equipment foundations, accent lighting, built-in tool benches, and qualifying office and customer-area fixtures). Lifts and air compressors themselves are equipment, depreciated on their own 5-year schedule.
• 15-year property (exterior paving, drainage systems, site lighting, and underground oil-water separators)
• 39-year property (the long-term shell of the building: roof, load-bearing walls, basic HVAC)

The reclassification matters because the faster you can depreciate something, the sooner you get the tax deduction. In plain terms: instead of waiting 39 years to recover the cost of the dedicated electrical serving your lifts and compressors, you can depreciate it over five years, or in the first year if bonus depreciation applies.

Faster deductions mean earlier tax savings, provided the deductions can be used against your income.

Why Auto Repair Shops Are Often Good Candidates

Auto repair facilities are often good candidates for cost segregation because of their investment in specialized buildouts and systems. Unlike a standard office building, these properties often include:

• Reinforced concrete for lifts and equipment pads
• Exhaust systems dedicated to shop equipment
• Oil and fluid storage installations
• Specialized lighting systems
• Expanded parking and drive lanes

Each of these is a candidate for a shorter recovery period, depending on how it’s built and used.

How Bonus Depreciation Fits In

Bonus depreciation lets businesses front-load deductions on certain property. Instead of waiting years to recover costs, you can deduct a large percentage of qualifying assets in the year they’re placed in service.

Cost segregation identifies the short-life assets in your property; bonus depreciation is what lets you deduct them right away.

Here’s the current schedule for shop owners:

• 2023: 80% bonus depreciation
• 2024: 60%
• January 1–19, 2025: 40%
• Property acquired and placed in service after January 19, 2025: 100% bonus depreciation, made permanent by the One Big Beautiful Bill Act

For example, take a $1.2 million facility buildout. If a cost segregation study identifies $300,000 of that as short-life property, and the property is acquired and placed in service after January 19, 2025, the owner can deduct the full $300,000 in the first year. If the deduction can be used, the tax savings can help fund new hires, another bay, or a second location.

Cost segregation identifies the short-life property; bonus depreciation determines how much of it can be deducted in year one.

Timing and Strategic Considerations

While cost segregation is most effective when done in the year of purchase or renovation, it can also be applied retroactively through a catch-up depreciation adjustment. This is particularly useful for shop owners who have owned their building for several years but have never considered a study. The IRS allows a “look-back” without amending past returns, which can unlock immediate deductions.

It’s also important to align the timing with your broader tax strategy. For example, if you anticipate higher revenue years ahead, you may want to coordinate the study to offset peak earnings. This is where the input of a tax professional becomes invaluable.

Getting More from Your Auto Repair Investment

For auto repair shop owners, the building is an operational asset. Cost segregation lets you recover its cost on the schedule each component actually qualifies for, rather than over 39 years by default.

By identifying which parts of your property qualify for accelerated depreciation, you can redirect savings into growing your business, upgrading equipment, or improving your bottom line.

If you’re considering how cost segregation for auto repair shops can improve your tax position, it’s worth working with a specialist.

R.E. Cost Seg prepares engineering-based studies for shop owners, following the IRS Cost Segregation Audit Techniques Guide.