Plan Your Home Addition with Confidence
Explore your project options, estimate your space requirements, organize your budget, and prepare for your next home improvement project.
Home Addition Planner
How this tool works
Calculations
Area = length × width, in feet. Base construction scenario = area × the cost per square foot you enter. Contingency = base × percentage ÷ 100. Scenario subtotal = base + contingency + any additional amounts you enter. Budget difference = planned budget − scenario subtotal.
Limits
This tool contains no construction price data and does not connect to a cost database, so every dollar figure comes from your own assumptions. Results are not a quote, a guaranteed cost, or a local market price. It cannot judge structural feasibility, zoning, permits, schedule or property value. Contact your local building department and qualified local professionals. Your answers stay in your browser and are not sent anywhere.