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Construction Cost Calculator

Build the budget the way a lender reads it — hard costs, soft costs, site work, and a contingency that is actually funded.

Heated living area
Materials + labor to build the structure
Purchase price of the lot
Design, permits, engineering, insurance, interest
Excavation, grading, septic/sewer, driveway
10% floor for new build, 15% for renovation
Leave 0 if building to hold
Free to use — we ask who you are only when you save.

What belongs in each line

Hard costs

Everything physically built: foundation, framing, roof, mechanicals, insulation, drywall, finishes, and the labor to install them. Quoted per finished square foot, hard cost varies enormously by market, finish level, and structure complexity — a simple rectangle with a gable roof costs far less per foot than the same square footage broken into wings and dormers.

Soft costs

The building doesn't get built without them: architecture and engineering, permits and impact fees, surveys, insurance during construction, legal, and construction-period interest. Ten to fifteen percent of hard costs is a common planning range, and it is the line most often left out entirely by first-time builders.

Site work

Excavation, grading, utility connections, septic or sewer, driveway, and landscaping. On a difficult lot this line can rival framing, and it is the one most likely to surprise you — which is why testing what you can before closing on land is worth the cost.

Contingency

Ten percent of hard costs is a floor for well-defined new construction; fifteen is prudent when scope is uncertain. A contingency is not padding — it is the line that lets you solve a problem in a day instead of a month, and on a construction loan, time is the most expensive input you have.

Cost per finished square foot

This is the number to compare across projects and against your market's comparable sales. If your all-in cost per square foot approaches what finished homes sell for locally, the project has no margin regardless of how good the build is.

Common questions

What percentage should soft costs be on a construction budget?

Ten to fifteen percent of hard costs is a common planning range for residential construction, covering design, permits, engineering, insurance, legal, and construction-period interest. Complex approvals or difficult jurisdictions push it higher.

How much contingency should a construction budget carry?

Ten percent of hard costs is a working floor for new construction with defined scope; fifteen percent is prudent for renovation or where site and structural conditions are unknown until work begins.

Does cost per square foot include land?

It depends on who is quoting. Builders usually quote hard cost per square foot excluding land. This calculator shows total project cost per finished square foot including land, which is the figure to compare against local sale prices.

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Calculator disclaimer

These interactive calculators are made available to you as self-help tools for your independent use. They are provided for general informational and illustrative purposes only and are not intended to provide financial, legal, tax, or investment advice. All examples are hypothetical. We cannot and do not guarantee their applicability or accuracy in regard to your individual circumstances, and results are estimates only — not a rate quote, a loan offer, an approval, or a commitment to lend. Actual terms, costs, and outcomes vary by borrower, property, and transaction, and all financing is subject to underwriting. We encourage you to seek personalized advice from qualified professionals regarding your project and your finances.