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Wall Area Calculator

Wall area is the total surface area of all walls in a room, calculated using the perimeter times height. It is the starting point for estimating paint, plaster, and drywall material needs.

What Is Wall Area?

Wall area is the total surface area of all walls in a rectangular room, calculated as twice the perimeter times height. It accounts for all four walls. Subtracting doors and windows gives the paintable area. Accurate wall area estimates are essential for paint, plaster, and drywall calculations.

Formula: 2 x (Length + Width) x Height

Example

Formula: 2 x (Length + Width) x Height
= 2 x (5 m + 4 m) x 2.8 m
= 50.40 m²

Enter room length, width, and height in any unit, then the result will be in m².

Tip: Choose your result unit on the right before calculating.

Step-by-step calculation

  1. Enter room length, width, and height with units.
  2. Select the result unit you want (m²).
  3. Calculate to see wall area and steps in the selected unit.

How this is calculated

Wall area = length times height, minus door and window openings; results convert across units.

Sources: IS 1200 (Method of Measurement of Building Works).

FAQ

How do I calculate wall area by hand?
Use 2 x (length + width) x height. Example: 2 x (5 + 4) x 2.8 = 50.4 m².
What is the formula for wall area?
Wall area = 2 x (Length + Width) x Height. Subtract doors and windows for paintable area.
Wall area vs room area
Wall area is vertical surfaces; room area is the floor only.
What units should I use?
Use meters for dimensions to get m². Convert cm by dividing by 100.
Can I use this for an irregular room?
Measure each wall separately, then add them together for total wall area.

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