Insulation Calculator

Calculate insulation materials and costs for walls and ceilings. Get accurate estimates for fiberglass, cellulose, spray foam, and mineral wool insulation.

100% Free • No Signup Required • Unlimited Use

Quick estimate mode (4 essential inputs). Toggle for 13 more professional options.

feet
Length of area to insulate
feet
Width of area to insulate
feet
Height of walls (for wall insulation)
Higher R-value = better insulation
Enter your ZIP code to adjust costs for your region
Adjusts material and installation costs based on local market conditions

Calculation Details

Wall Area = (Length + Width) × 2 × Height × 0.85 (door/window reduction)
Ceiling Area = Length × Width
Includes vapor barrier and installation costs
Energy savings are estimated based on improved thermal performance