Most home build budgets start with a builder's price per square foot. That number covers the house. It usually does not cover the land, the design and permit fees, or the cushion you need when something changes. This calculator adds those back, so the first number you plan around is an honest one.
Common buffer
10-15%
contingency on the construction cost
Often missed
8-12%
added by design, permits, engineering, and fees
The real check
Loan + cash
compared against the full project cost
Use the calculator
Estimate the total cost of building your home.
Enter the home size and your builder's quoted cost per square foot, then add land and fees. Put in your construction loan and the cash you have available to see whether they cover the full project, or how far short they fall.
Core build
Start with the main quote.
Use the builder quote for the house, then add land and soft costs around it.
Funding & cushion
Add your funding and reserve.
Check whether your loan and cash cover the estimate, then layer in contingency as your cushion for overruns.
Estimated total project cost
$685,000
Includes the quote, land, design and permit costs, plus 10% contingency on the build.
Quote
$600,000
Land
$0
Fees
$25,000
Contingency (10%)
$60,000
Add your funding and reserve to see whether your funding covers this estimate.
Next step
When the estimate looks right, the next job is keeping budget, funding, and affordability connected.
What the estimate includes
- Construction cost: home size times the quoted cost per square foot.
- Land: enter 0 if you already own the lot.
- Design, permits, and fees: plans, engineering, surveys, permits, and loan fees. These soft costs often add 8 to 12% on top of construction.
- Contingency: a percentage of the construction cost. Land is a settled price and fees rarely move, so contingency is not applied to them.
- Funding check: your construction loan plus available cash, compared with the total.
What to add before you commit
A quick estimate is a starting point, not a budget. Before you sign with a builder or lock a loan amount, check for the costs that sit outside a per-square-foot quote. Site work is the big one: driveway, grading, septic or sewer, well or water, and utility connections can move the total a lot, especially on rural lots.
Construction loan interest is the other. During the build you usually pay interest on what has been drawn, and that cost grows as the project moves. The construction loan interest calculator estimates it from your loan size, rate, and build length.
From a first estimate to a budget you can track
Once the build is real, the estimate becomes a working construction budget: categories, allowances, a contingency line, and actual costs arriving every month. That is where Groundbase, a home building budget app for homeowners, picks up. It tracks actual costs and change orders against the budget and connects them to your funding, construction loan draws, interest, and finished mortgage payment.