Which Home Improvements Count as Capital Improvements?
The purpose of this article is to identify which home improvements may reduce taxes by lowering your taxable gain when you sell.
In the first article of this series, The Massachusetts Tax Trap Hiding Inside Your Home Sale, John and Mary sold their Wellesley home for $2,100,000.
As a married couple filing jointly, John and Mary faced an estimated tax exposure of $278,950.
Fortunately, that initial estimate did not account for several potential adjustments that may reduce taxable gain, including qualifying capital improvements, purchase costs, and selling costs.
To see how these adjustments can reduce John and Mary’s taxable gain, let’s review a simplified version of the calculation (you can also estimate your overall walk-away numbers using our Wellesley net proceeds guide):
Now that the calculation is clear, let’s look at which home improvements may qualify as capital improvements and which projects are generally treated as routine repairs. Understanding the difference can help you document eligible upgrades and build your adjusted basis before you sell.
Qualifying Capital Improvements vs. Routine Repairs
Under IRS rules, a home project may increase your adjusted basis when it:
- Adds value to the home
- Prolongs the home’s useful life
- Adapts the home to a new use
Routine repairs and maintenance generally do not increase your adjusted basis. They typically keep the home in normal operating condition rather than materially improving it.
The scope of the work matters. For example, replacing a broken windowpane by itself is generally considered a repair. In contrast, replacing that same window as part of a whole-house window replacement project is generally treated as a capital improvement.
The comparison below shows how common New England home projects are generally categorized. Tracking these costs is especially important as inflation continues to affect Greater Boston real estate and construction costs.
| Project Category | Qualifying Capital Improvements | Routine Repairs |
|---|---|---|
| Roofing & Siding | Installing a new roof or new siding | Patching a leak or replacing a few shingles |
| Heating & Cooling (HVAC) | Installing a new HVAC system or adding central air conditioning | Annual furnace or air-conditioning tune-ups |
| Kitchens & Bathrooms | Completing a kitchen or bathroom renovation | Painting an interior room or patching drywall |
| Decks & Outdoor Living | Building a new deck, patio, porch, or permanent fence | Replacing a single rotted deck board |
| Basements & Attics | Finishing an unfinished basement, attic, or crawlspace | Recaulking a bathtub or fixing a broken windowpane |
| Windows & Efficiency | Replacing windows throughout the home or adding new insulation | Fixing a leaky faucet or replacing a toilet valve |
| Driveways & Garages | Paving an unpaved driveway or expanding a garage | Sealing or patching cracks in an existing driveway |
FAQ: Archiving Your Home Improvement Records
What If I Can’t Find My Original Renovation Receipts?
You aren't entirely out of luck. While original itemized receipts are the gold standard, you can reconstruct a paper trail to substantiate your basis adjustments to the IRS. Gather supporting evidence from these key sources:
- Town Building Permits & Certificates of Occupancy: Documents the official timeline and scope of major structural upgrades.
- Bank & Credit Card Statements: Shows historical line-item payments made directly to contractors, architects, or home improvement retailers.
- Dated Photos: Before-and-after snapshots visually confirm major renovations or additions.
- Contractor Records: If the business is still active, request duplicate invoices or a signed statement verifying the project details.
What Specific Documentation Should I Save for New Projects?
To protect your investment, retain a "triad of proof" for every major upgrade. Your records must verify three core components:
- The Scope: A signed contract, estimate, or itemized invoice detailing exactly what was built or replaced to prove it qualifies as an improvement, not a routine repair.
- The Payment: A canceled check, credit card statement, or bank confirmation verifying the total amount paid.
- The Completion: Final permits, official inspection sign-offs, completion photos, or manufacturer warranties.
Bundling these components together gives your CPA a documented record to securely reduce your taxable gain when you sell.
How Should I Organize My Property Capital Improvements Data?
Create a dedicated "Basis Binder"—either a physical folder or a digital archive (Google Drive, Dropbox, etc.)—to track your upgrades. Group your documents using one of two strategies:
- Chronologically by Year: Create folders named by project and date (e.g., 2015 – Kitchen Renovation, 2022 – New Roof). Keep the contract, permits, invoices, and payment receipts bundled together inside.
- By Category: Organize folders by system type: Exterior & Structural (roof, siding, windows, decks), Mechanical Systems (HVAC, furnace, water heater), and Interior Remodels (kitchens, baths, flooring).
The goal is to provide your CPA with a clear document trail that safely minimizes your taxable gain when you list your home.
How Long Do I Need to Keep These Tax Records?
Before the Sale: Keep all home improvement records for as long as you own the property. Unlike ordinary annual tax returns, these documents are required to establish your adjusted basis.
After the Sale: Retain all documentation for at least three years from the official due date of the tax return reporting the sale. For example, if you report a 2026 home sale on your return due in April 2027, you must securely store your records until at least April 2030.
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Part 3: How Purchase and Selling Costs Impact Your Taxable Gain
Learn how certain purchase costs may increase your adjusted basis—and how qualifying selling costs may reduce the amount realized on your home sale.
Disclaimer: This article is for informational purposes only and is not tax or legal advice. Whether a cost increases adjusted basis depends on the facts of the project, available documentation, prior tax treatment, possible credits or subsidies, and other applicable rules. Always consult a certified public accountant or qualified tax professional before finalizing a real estate transaction or reporting a home sale.
