RenoCalc.com

Home Addition Cost Calculator

Get an instant estimate for your home addition. Adjust size, materials, foundation type, and region to see a personalized cost breakdown.

Home Addition Cost Calculator

Estimate the cost of adding square footage to your home based on size, materials, and foundation type.

100 sq ft1,000 sq ft

Estimate Breakdown:

Base: $37,000 | Range: $27,750$49,950

*Permits, architectural fees, and utility connections not included.

How to Use This Calculator

  1. Enter your addition size in square feet.
  2. Select your material quality tier.
  3. Choose your foundation type.
  4. Select your region for localized labor costs.
  5. Review your personalized low/average/high estimate.

Frequently Asked Questions

How accurate is this home addition calculator?

Our calculator provides estimates based on national averages. Actual costs may vary by 25–35% depending on your contractor, architectural complexity, and local permitting costs.

Does the estimate include architectural fees?

No. Our estimate covers construction costs only. Architect or designer fees typically add 5–15% of the construction budget.

Do I need a permit for a home addition?

Yes. Virtually all structural additions require a building permit. Budget $500–$3,000 for permits depending on your municipality and project scope.