What it calculates
Calculate wall area minus doors and windows.
Paintable Wall Area Calculator
Calculate wall area after subtracting doors and windows.
Planning and estimating aid only. Verify project requirements, manufacturer instructions, adopted codes, permits, and field conditions before performing regulated work.
Painting estimating
How to Use This Calculator
Enter the measurements and job information you know, select Calculate, then use the result as a starting point for estimating, purchasing or project planning.
How the calculation works
Gross wall area = room perimeter × wall height. Door and window areas are subtracted.
What the result means
For irregular rooms, calculate separate wall sections and combine them.
From room dimensions to net wall area
A 12 × 10-foot room with 8-foot walls has 2 × (12 + 10) × 8 = 352 square feet of gross wall area. Subtract 21 square feet of door area and 11 square feet of window area to get 320 square feet of net wall area.
Contractor tip: Break irregular rooms into measured wall sections. Sloped ceilings, partial-height walls and large openings may require separate measurements rather than one rectangular-room calculation.
Verify the final quantity
Coverage varies with surface texture, porosity, color change, application method and product. Use the coating manufacturer's stated spread rate for final purchasing.
Good practice: Compare the calculated quantity with plans, specifications, product packaging and current field conditions before purchasing material.