Bump-Out Addition Cost Calculator
Estimate the cost of a bump-out addition based on size, foundation type, finish level, and your location.
Last updated: March 25, 2026
Bump-Out Addition Cost Calculator
Estimate the cost of a bump-out addition based on size, foundation type, finish level, and your location.
Estimated Total
$21,500
Itemized Breakdown
This calculator provides estimates based on national averages adjusted for your region. Actual costs may vary significantly based on specific project conditions, contractor availability, material prices, and local market factors. Always get at least 3 quotes from licensed, insured contractors before starting your project.
Want the full picture?
Read our complete Bump-Out Addition cost guide with material comparisons, contractor tips, savings strategies, and regional pricing data.
Quick Cost Reference
Cost by Tier
Small 60-80 sq ft bump-out, cantilevered over existing foundation, no foundation work needed, standard materials matching existing siding.
100-150 sq ft bump-out with foundation piers or slab extension, mid-grade finishes, energy-efficient windows, basic electrical.
200+ sq ft bump-out with full concrete foundation, premium materials, custom windows, dedicated heating/cooling, high-end finishes.