How to Budget a Home Renovation

Mid-range whole-home renovation in 2026 runs $90 to $230 per square foot in most US metros, with major metros (San Francisco, NYC, Boston, LA) running $180 to $360. Kitchens run $200 to $480 per square foot, with bathrooms slightly higher at $250 to $520 per square foot.

Additions cost more because they include foundation, framing, and a full envelope. Mid-range additions run $200 to $400 per square foot. Custom-build new construction in 2026 runs $250 to $550 per square foot for mid-range, $500 to $900 for premium.

These benchmarks are starting points. Your local market, your finish tier, and your project's complexity all move the number. Pull two or three actual bids before locking the budget.

Renovation cost overruns are mostly hidden-condition discoveries: rotten subfloor under tile, knob-and-tube wiring behind drywall, asbestos in the popcorn ceiling, undersized water main. Contingency is the budget cushion that lets these discoveries get fixed without breaking the project.

Newer homes (post-2000) usually need 10 to 12% contingency. Mid-age homes (1970 to 1999) need 12 to 15%. Older homes (pre-1970) need 15 to 22%. Going below 10% on any renovation is a budget mistake that almost always gets paid for later through credit-card debt or stalled scope.

Permit fees vary widely by jurisdiction. Most suburbs charge a flat permit fee plus a per-square-foot review fee, often totaling 0.5 to 2% of construction cost. Design-review zones in city centers can add 2 to 4% in design review fees on top of standard permits.

Architectural and engineering fees run 4 to 12% of construction cost depending on project complexity. A simple kitchen remodel may need only a kitchen designer (often $1,500 to $4,500 fixed), while a major addition needs an architect ($8,000 to $40,000) plus a structural engineer ($2,000 to $8,000).

Budget for both upfront. Surprise design fees mid-project are a top-five overrun source.

The four common financing paths are cash, home equity line of credit (HELOC), cash-out refinance, and renovation loan (FHA 203(k) or Fannie Mae HomeStyle). Each has tradeoffs: cash is simplest but ties up liquidity, HELOC is flexible but variable-rate, cash-out refi locks the rate but resets the mortgage, and renovation loans roll project cost into the mortgage but require more paperwork.

Whichever path you choose, confirm availability before signing the contract. The contractor's draw schedule needs to match your financing release schedule so the contractor never waits on a slow lender. Mismatch between draw schedule and lender release is a top cause of project delays.

The five most-forgotten budget line items are temporary housing (if the kitchen or only bathroom is offline), storage of furniture and household goods during demo, design and permit fees, sales tax on materials (often invisible until the final invoice), and the contingency itself.

A $80,000 kitchen renovation that ignores these can quickly become $94,000 once you factor in $4,000 of temporary housing, $1,500 of storage, $2,000 of design fees, $4,000 of state and local sales tax, and a draw on contingency for one hidden-condition discovery. Build all five into the starting budget.

The simplest tracking method is a spreadsheet with three columns: budget category, budgeted amount, and actual paid. Update weekly. Anything tracking 5% or more above budget gets a flag and a conversation with the GC.

Project-management platforms automate this. ContractShield's project workspace tracks every paid draw against the budget category, surfaces variance in real time, and links each variance to the source change order or invoice. The result is real-time budget visibility instead of monthly surprise.