A broken window feels like a repair, and sometimes it is. You had a working window, it cracked, you paid to get a working window back. But the tax code draws a sharp line between fixing a window or two and replacing every window in the house, and that line decides whether you deduct the whole bill this year or spread it across nearly three decades. The expensive mistake I keep seeing on self-managed returns is a whole-house window job written off in full as a repair, which is one of the loudest audit flags on a rental return and rarely holds up under a second look.
The short answer: windows and doors are structural components of the building, so a replacement that has to be capitalized takes a 27.5-year life, straight line, mid-month convention, the same schedule as the building it sits in. The longer answer is where the money lives: when a window or door job is a deductible repair instead, how the de minimis safe harbor can rescue a small job, and the write-off for the old units that almost everyone forgets.
The class life: 27.5 years as a structural component
Windows and doors are not separate equipment with a short life of their own. Treasury Regulation 1.48-1(e)(2) lists “windows and doors” by name as structural components of a building. Under IRS Pub 527 Table 2-1, residential rental property and its structural components are 27.5-year property under the general depreciation system. So a capitalized window or door replacement inherits the building's 27.5 years, depreciated straight line with the mid-month convention, rather than getting a faster recovery period.
The job is treated as separate property placed in service when the work is finished, not when you bought the building. Say you own a duplex and replace all the windows for $13,200 in a year, with the install finished in April. That $13,200 starts its own 27.5-year straight-line schedule, using the mid-month convention for April. Once the schedule is steady the annual deduction is roughly $480, and the first year is prorated by the mid-month factor for an April in-service date. The math is the same engine behind any building improvement, so the 27.5-year depreciation walkthrough covers the mechanics in full, and you can sanity-check a number with the depreciation calculator.
Repair or improvement: where the line actually sits
Not every window touch is a capital improvement. Replacing one or two broken windows, or rehanging a damaged door, to bring the unit back to its ordinary operating condition is a currently deductible repair. You deduct it in the year you pay it. The change happens when the work crosses from fixing a part to bettering or restoring a major component of the building.
The tangible property regulations frame this as the BAR test: betterment, adaptation, or restoration. A whole-house window replacement is a restoration because you replaced a major component in its entirety, and often a betterment too if the new units are a material upgrade. That is why a single cracked pane is a repair and a forty-window job is 27.5-year property, even though both are “windows.” If you want the framework applied to twenty common line items, the repairs versus improvements guide walks through the calls one by one.
- Deductible repair: one or two broken windows replaced, a damaged door rehung, weatherstripping or a single sash fixed to restore ordinary condition.
- Capitalized improvement: a whole-house window replacement, or a window-and-door package that betters or restores a major component, depreciated over 27.5 years.
- Storm windows and doors: Pub 527 Table 1-1 lists them as examples of improvements, so adding them is a capital cost, not a current deduction.
The de minimis safe harbor: the per-item rescue
A small window or door job that would otherwise be capitalized can sometimes be expensed under the de minimis safe harbor. The safe harbor is judged per item or per invoice line, not on the total of the invoice, with a $2,500 limit per item for a taxpayer without an audited financial statement. If a vendor lists each window separately and each one is at or under $2,500, several windows on one invoice can each qualify, even though the bill as a whole is larger.
Two conditions matter. You need the de minimis election filed with the return for that year, and you need the invoice to itemize per unit rather than quote one lump sum. Ask the vendor to break out the cost per window or per door on the bill. That single formatting choice can turn a 27.5-year deduction into a current one for the smaller jobs. The same logic does not stretch to a true whole-house replacement, which is a restoration regardless of how the lines are priced.
The old windows: claim the partial disposition
When you capitalize a window replacement, the windows you tore out still have undepreciated basis sitting on your books if they were part of the original building cost. The partial disposition election lets you write off that remaining basis in the year you remove them. Skip it and you end up depreciating two sets of windows at once, the gone ones and the new ones, which inflates your basis for years and quietly costs you at sale through higher depreciation recapture.
The election has to be made on a timely filed return for the year of the replacement, which is the practical reason it gets missed: by the time anyone notices the double count, the window has closed. If your original building basis is one undivided number, estimating the slice attributable to the old windows takes a reasonable allocation method, and this is a good spot to hand the math to your CPA rather than guess.
Two watch-outs before you file
First, the whole-house window job expensed as a repair. It is a top audit flag precisely because it is so tempting: the bill is large, the word “repair” is on the invoice, and the deduction is immediate. A restoration of a major component does not become a repair because the contractor called it one. If you replaced every window, plan on capitalizing it.
Second, the energy credit that does not apply. The 25C energy efficient home improvement credit is for a home you live in, so efficient windows on a rental you do not occupy do not earn it. On a rental, those windows are 27.5-year property like any other window job. Do not let an installer's homeowner-credit pitch shape how you treat the cost on a Schedule E rental.
Getting it onto your return cleanly
All of this lands on Schedule E: the deductible repairs flow to line 14, and the capitalized replacement adds a 27.5-year asset that feeds depreciation on line 18. The trick is keeping the two buckets separate all year so a window invoice is already labeled repair or improvement before tax season, rather than a pile of receipts you sort under deadline. I built rents.ai to flag the capital items into their own 27.5-year schedules and keep line 18 current as you go, though it produces estimates to organize your year for your CPA and does not file your return or make the repair-or-improvement call for you. Whichever tool you use, the win is deciding the call once, in the month the work is done.
These figures are estimates to help you organize your year for your CPA, not tax advice. Recovery periods, the de minimis safe harbor, and the partial disposition election are governed by IRS Publication 527 and the tangible property regulations under Treasury Regulation 1.48-1(e)(2). Confirm how any specific window or door job should be treated with a tax professional before you file.