This is the complete list of building components classified by IRS depreciation category, pulled from our engineering database. Bookmark it. Your CPA will thank you.
A cost segregation study takes a building and breaks it into its individual components, then classifies each one by its IRS recovery period under MACRS. Instead of depreciating the entire building over 27.5 years (residential) or 39 years (commercial), you pull out the pieces that qualify for 5-year, 7-year, or 15-year recovery. With 100% bonus depreciation restored permanently under the One Big Beautiful Bill Act (2025+), those reclassified components are deducted in full in Year 1.
The tables below are the components. If you want context on what percentages to expect by property type, see our percentages breakdown. If you want to understand the difference between standard and accelerated depreciation, we have that too. This page is just the list.
How to read the confidence column: Common means it is classified this way in virtually every study—no debate. Typical means the classification holds in most cases, but facts and installation method matter. Judgment call means it depends on context, installation, or auditor interpretation.
5-Year Personal Property
These are "tangible personal property" and certain "special purpose structures" under IRC §1245. The classification test: could you remove it without damaging the building? If yes, it is probably 5-year property. These components typically represent 15–25% of a property's depreciable basis, depending on type and condition. See our benchmarks data for specifics.
| Component | Description | IRS Basis | Confidence |
|---|---|---|---|
| Carpet & Pad | Wall-to-wall carpeting with padding—removable without damage to building | Reg 1.48-1 | Common |
| Vinyl/Laminate Flooring | Vinyl plank, laminate, resilient flooring—not permanently affixed | Reg 1.48-1 | Common |
| Appliances | Range/oven, refrigerator, dishwasher, microwave, disposal | 00.11 | Common |
| Light Fixtures | Decorative ceiling fixtures, recessed lighting cans, under-cabinet lights | 00.11 | Common |
| Window Treatments | Blinds, shades, curtain rods—removable decorative elements | Reg 1.48-1 | Common |
| Ceiling Fans | Ceiling-mounted fans with light kits | 00.11 | Common |
| Removable Kitchen Fixtures | Freestanding islands, removable range hoods, specialty fixtures | Reg 1.48-1 | Typical |
| Bathroom Accessories | Medicine cabinets, removable vanity tops, accessories | Reg 1.48-1 | Typical |
| Removable Laminate Surfaces | Removable laminate and modular countertop surfaces | Reg 1.48-1 | Typical |
| Door Hardware & Accessories | Locksets, hinges, closers, door stops | Reg 1.48-1 | Common |
| Smoke/CO Detectors | Smoke detectors, carbon monoxide detectors | 00.11 | Common |
| Closet Shelving | Wire or wood closet organizer systems—removable without structural damage | Reg 1.48-1 | Typical |
| Decorative Millwork | Crown molding, chair rail, wainscoting (decorative, not structural) | Reg 1.48-1 | Judgment call |
| Specialty Electrical | Doorbell system, structured wiring for cable/phone/data | 00.12 | Common |
| Bathroom Hardware | Towel bars, toilet paper holders, robe hooks, shower rods | Reg 1.48-1 | Common |
| Kitchen Hood & Ventilation | Range hood, exhaust fan, ventilation equipment | 00.11 | Common |
| Removable Plumbing Trim | Removable faucet trim, showerheads, supply stops | Reg 1.48-1 | Typical |
| Pool Equipment | Pool pump, filter, heater—removable mechanical equipment | 00.11 | Common |
| Garage Door Opener | Automatic garage door opener system | 00.11 | Common |
| Security/Access Control | Card readers, cameras, alarm system—removable electronic | 00.12 | Common |
| Solar Panel System | Rooftop solar photovoltaic system | 48.14 | Common |
STR / Furnished Property Additions
If the property is furnished—an Airbnb, vacation rental, or furnished long-term rental—these components also qualify as 5-year personal property. Yes, your decorative barn door is 5-year property. The IRS does not care that it cost $3,000 from Restoration Hardware. This is why STRs consistently hit higher accelerated percentages than unfurnished rentals: there is simply more 5-year property to reclassify.
| Component | Description | IRS Basis | Confidence |
|---|---|---|---|
| Bedroom Furniture | Beds, mattresses, dressers, nightstands, headboards | 00.11 | Common |
| Living Room Furniture | Sofas, tables, chairs, entertainment centers | 00.11 | Common |
| Dining Furniture | Dining table, chairs, bar stools | 00.11 | Common |
| TVs & Electronics | Smart TVs, streaming devices, sound bars | 00.11 | Common |
| Linens & Bedding | Sheets, comforters, pillows, towels | 00.11 | Common |
| Kitchen Smallwares | Pots, pans, dishes, utensils, small appliances | 00.11 | Common |
| Outdoor Furniture | Patio furniture, outdoor dining set | 00.11 | Common |
7-Year Property
Seven-year property is the smallest category. Most items that investors think are 7-year are actually 5-year. The distinction matters because under bonus depreciation the deduction is the same (100% in Year 1), but the underlying recovery period affects certain elections and recapture calculations.
| Component | Description | IRS Basis | Confidence |
|---|---|---|---|
| Decorative Items & Artwork | Wall art, mirrors, decorative accessories, lamps, throw pillows, rugs | 00.11 | Common |
| Exterior Signage | Freestanding monument signs, building-mounted signage | 00.11 | Common |
| Elevator Controls | Control panels, dispatch system, monitoring electronics | 00.12 | Typical |
Note: The elevator cab, shaft, and machinery are 27.5/39-year structural property. Only the electronic controls and dispatch system qualify for 7-year treatment.
15-Year Land Improvements
Everything outside the building footprint that is not raw land. These are classified under Asset Class 00.3 (Land Improvements) and depreciated over 15 years—or deducted in full in Year 1 under bonus depreciation. For many properties, particularly those with large lots, extensive hardscaping, or pools, the 15-year bucket is where the biggest dollar amounts hide.
| Component | Description | IRS Basis | Confidence |
|---|---|---|---|
| Concrete Paving & Walks | Driveway, walkways, patio slabs | 00.3 | Common |
| Asphalt Paving | Asphalt driveway and parking areas | 00.3 | Common |
| Fencing | Wood, vinyl, chain-link, or metal fencing | 00.3 | Common |
| Landscaping | Trees, shrubs, ground cover, mulch beds | 00.3 | Common |
| Irrigation System | Sprinkler system, drip irrigation | 00.3 | Common |
| Exterior Lighting | Landscape lighting, pathway lights, security lights | 00.3 | Common |
| Retaining Walls | Decorative and structural retaining walls | 00.3 | Typical |
| Wood Deck/Porch | Exterior wood or composite decking, covered porches | 00.3 | Common |
| Storm Drainage | Site grading, swales, French drains | 00.3 | Common |
| Swimming Pool | In-ground swimming pool | 00.3 | Common |
| Pool Decking | Concrete/stone pool deck | 00.3 | Common |
| Pergola/Gazebo | Freestanding pergola, gazebo, shade structure | 00.3 | Common |
27.5-Year / 39-Year Property (The Structural Shell)
Everything not in the tables above stays on the default schedule: 27.5 years for residential rental property, 39 years for commercial. This is the building itself—foundation, framing, roofing, exterior walls, windows (the glass and frame, not the treatments), main HVAC system, plumbing risers, electrical mains, and drywall. A cost segregation study does not make these go away. It just identifies everything that is not structural and pulls it into a shorter recovery period.
The practical effect: on a typical single-family rental, 75–85% of the depreciable basis stays at 27.5 years. That is not a failure of the study. That is the building being a building. The value comes from the 15–25% that gets accelerated—and the Year 1 tax impact of deducting that full amount immediately.
The Gray Zone
Not every component falls neatly into a category. Some classifications depend on how the item was installed, what it is attached to, or how aggressive your tax professional wants to be. Here are the three gray areas that come up most often.
Decorative Millwork
Crown molding is technically decorative (5-year) but some auditors argue it is integral to the wall finish (27.5-year). We classify it as 5-year with a judgment-call flag because the weight of case law supports it, but your CPA should know it is debatable. The IRS Cost Segregation Audit Techniques Guide acknowledges decorative finishes as potentially shorter-lived property, but does not draw a bright line. Wainscoting and chair rail fall into the same bucket. If the molding is purely ornamental and could be removed without altering the structural integrity of the wall, the 5-year argument is strong. If it is load-bearing trim integrated into a built-in (rare, but it happens in older homes), it is not.
Built-In vs. Freestanding
The magic word is "removable." A freestanding kitchen island is 5-year. The same island bolted to the floor with a gas line running to it? That is 27.5-year. A wall-mounted TV bracket is 5-year. A custom media wall with integrated cabinetry, recessed lighting, and drywall returns? That is part of the building. Your contractor's invoice and installation method determine the classification, not the item itself. This is why we flag "Removable Kitchen Fixtures" as Typical rather than Common—the answer genuinely depends on how it was built.
HVAC Components
The system itself (furnace, AC condenser, ductwork) is 27.5-year. Full stop. But the thermostat? The removable grilles? Some firms classify those as 5-year. We do not—the dollar amounts are trivial (a Nest thermostat allocated at $12/unit in a cost study) and it is not worth the audit risk. If an IRS examiner is reviewing your $400K cost seg study and sees you reclassified $36 worth of return air grilles, it does not inspire confidence in the rest of your analysis. We would rather give up $50 in deductions and keep the study bulletproof.
Why This Matters Financially
Abstract component lists are useful for CPAs and tax nerds. For everyone else, here is what it looks like in dollars.
Scenario: a $1M single-family rental, 8,000 SF, built in 2005.
Take one component: decorative lighting. Our cost database allocates interior light fixtures at approximately $1.45/SF for a mid-quality residential property of this vintage. On 8,000 SF, that is $11,600 allocated to decorative lighting.
| One Component: Decorative Light Fixtures ($11,600) | |
|---|---|
| Without cost seg (27.5-year straight-line) | $422/year in depreciation |
| With cost seg (5-year, 100% bonus) | $11,600 deducted in Year 1 |
| Year-1 difference at 37% bracket | $4,136 in additional tax savings |
That is $4,136 from one component. A typical cost segregation study reclassifies 15–20 components. The light fixtures are not even the biggest line item—carpeting, appliances, and land improvements each carry more weight. When you stack all of them together, a $1M SFR typically produces $60,000–$80,000 in Year 1 deductions from components that would otherwise trickle out at $2,000–$3,000 per year over 27.5 years.
For a deeper look at the Year 1 math, see our first-year depreciation guide.
How We Classify
Our component classifications are based on IRS Rev. Proc. 87-56 asset class guidelines, the IRS Cost Segregation Audit Techniques Guide (Chapter 7), and RSMeans 2024 national construction cost data. We use a conservative approach: when classification is ambiguous, we note it as a judgment call rather than asserting certainty.
Every study we produce includes component-level detail with IRS asset class citations, cost allocations per square foot, and the specific depreciation schedule for each item. The goal is a report your CPA can file without second-guessing the classifications—and that holds up if the IRS ever reviews it.
More from the Blog
Cost Segregation Percentages: What to Actually Expect by Property Type
Real reclassification percentages from our studies: SFR 15-20%, STR 20-30%, multifamily 18-28%, commercial 20-35%.
Cost Segregation vs. Standard Depreciation: The Real Difference
27.5 years of straight-line depreciation vs. accelerated recovery periods. Here is what changes and why it matters.
Cost Segregation Benchmarks: How Your Property Compares
Benchmark data across property types, price ranges, and geographies. See where your property falls.