Real Estate & Investing
Rehab Budget Calculator
Build a renovation budget from individual trade line items, add a contingency allowance, and see the cost per square foot.
Calculation inputs
Leave a line at zero if it is not part of the scope.
Results
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Complete the fields and select Calculate to show results here.
About this calculator
This calculator totals a renovation scope by adding individual trade line items, applying a contingency allowance, and dividing by square footage to show cost per square foot. It helps investors and homeowners build a realistic rehab budget before committing to a project or making an offer that depends on it.
How the calculation works
- Subtotal = sum of all trade line items
- Contingency = subtotal × contingency %
- Total budget = subtotal + contingency
- Cost per sq ft = total budget ÷ square footage
Notes and assumptions
A 10% contingency is a common starting point for cosmetic work; structural or older properties often warrant 15–20%.
Cost per square foot is a quick sanity check against similar renovations in the same market.
How it works in plain English
Each trade category — roof, HVAC, kitchen, bathrooms, flooring, paint, electrical, plumbing, and landscaping — is entered as a separate dollar figure, and any line not part of the scope can be left at zero. Adding all of these together produces the subtotal for the project.
A contingency percentage is then applied to the subtotal to account for the unexpected costs that show up once work begins, such as hidden water damage or outdated wiring. The contingency amount is added to the subtotal to arrive at the total budget.
If square footage is provided, the calculator divides the total budget by that figure to show cost per square foot, which is a quick way to sanity-check the scope against similar renovation projects in the same market. The tool also flags the single largest line item, since that is often where budget overruns concentrate.
The formula
- Subtotal = sum of all trade line items
- Contingency = subtotal x contingency %
- Total budget = subtotal + contingency
- Cost per sq ft = total budget / square footage
Worked example
A renovation scope includes $9,000 for roofing, $7,500 for HVAC, $14,000 for the kitchen, $9,000 for bathrooms, $6,500 for flooring, $4,000 for paint, $5,500 for electrical, $5,000 for plumbing, and $2,500 for landscaping, totaling a $63,000 subtotal.
With a 10% contingency, that adds $6,300, bringing the total budget to $69,300. On a 1,600 square foot home, that works out to about $43.31 per square foot, and the kitchen at $14,000 stands out as the largest single line item in the scope. That per-square-foot figure can be compared against typical renovation costs for similar homes in the area; if local comparable projects run closer to $55 to $65 per square foot, this scope might be missing work, while a much higher local benchmark could suggest there is room in the budget for upgrades beyond the current plan.
Typical contingency allowances by project type
| Project type | Common contingency |
|---|---|
| Cosmetic updates (paint, flooring, fixtures) | 5% - 10% |
| Moderate renovation (kitchen, bath, systems) | 10% - 15% |
| Structural or older-property renovation | 15% - 20%+ |
Reflects common industry rules of thumb for renovation budgeting; actual needs vary by property age and condition.
Frequently asked questions
How much contingency should I budget?
A 10% contingency is a common starting point for straightforward cosmetic work, while structural repairs, older homes, or properties with unknown conditions behind walls often warrant 15% to 20% or more. The right figure depends on how much uncertainty exists about the property's current condition.
What is cost per square foot useful for?
Cost per square foot lets you quickly compare a proposed budget against typical renovation costs for similar homes in the same market. If your figure is far outside the normal range for comparable projects, it is worth reviewing individual line items for errors or missing scope.
Should I include labor and materials separately?
The calculator does not require that distinction; each line item can represent the combined cost of labor and materials for that trade, which is how most contractor bids are structured. If you have separate labor and material estimates, simply add them together before entering the line total.
What if a category isn't part of my project?
Leave that line at zero. The calculator only totals the categories with a value entered, so a cosmetic-only project can skip roof or HVAC entirely without affecting the accuracy of the subtotal, contingency, or total budget calculation.
Does this budget include permit fees or design costs?
Not automatically. Permit fees, architectural or design fees, and inspection costs are not built into the standard trade categories, so they should be added as part of one of the line items or accounted for separately outside this budget if they apply to your project.
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