How to Calculate Wall Square Footage
Find the total surface area of your walls for paint, drywall, or wallpaper projects.
Calculating wall square footage is the first step in any interior renovation. This determines how much paint, wallpaper, or drywall sheets you need to purchase.
The Wall Formula
Total Wall Area = (Wall Length x Wall Height) - Area of Doors/Windows. Subtracting openings is crucial for accurate material estimation.
Net Square Footage
A standard 3x7 foot door takes up 21 square feet. A standard 3x5 window takes up 15 sqft. Subtracting these openings can save you 15-20% on paint costs if your room has multiple windows and doors.
Industry data feed active. Integrated sponsor slots reserved for verified partners.
Support the Blueprint
DIYLookup is built for builders by builders. Help us keep the math open-source and the site ad-free by supporting our mission.