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Home, building & household

Wall area

Calculate wall area of a rectangular room minus openings.

Your result

Complete the fields and calculate.

Calculation method and formula

2 × (Room length [m] + Room width [m]) × Room height [m] − Doors & windows [m²]

Understand the inputs

Room length
Unit: m. Use a measured value or your own assumption.
Room width
Unit: m. Use a measured value or your own assumption.
Room height
Unit: m. Use a measured value or your own assumption.
Doors & windows
Unit: m². Use a measured value or your own assumption.

Assumptions and limitations

The model assumes the simple geometry shown. Measure lengths in the stated units. Split irregular areas into separate shapes and count openings only once.

The formula uses the specified units. Displayed numbers are rounded; whole packs, item counts and full time periods may also be rounded within the calculation.

Worked example

Illustrative values. Replace them with your own inputs for your calculation.

Room length
5 m
Room width
4 m
Room height
2.6 m
Doors & windows
5 m²
Example result41.8 m²

The result was calculated directly from your entries.

Model revision: October 17, 2026 · How CleverCalc works

FAQ

Frequently asked questions

How does Wall area work?+

2 × (Room length [m] + Room width [m]) × Room height [m] − Doors & windows [m²]. The model assumes the simple geometry shown. Measure lengths in the stated units. Split irregular areas into separate shapes and count openings only once.

What assumptions should I consider for this result?+

The model assumes the simple geometry shown. Measure lengths in the stated units. Split irregular areas into separate shapes and count openings only once. The formula uses the specified units. Displayed numbers are rounded; whole packs, item counts and full time periods may also be rounded within the calculation.

How accurate is the result?+

The formula uses the specified units. Displayed numbers are rounded; whole packs, item counts and full time periods may also be rounded within the calculation. Prices, measurements and model assumptions determine how well the result represents your situation.

Is this calculator free?+

Yes. Calculations and PDF export work without an account or registration.

What happens to my inputs?+

Calculations run in your browser. Results are saved locally only when you add them to My results; favourites and history are also local. Shared links contain your values. The currency tool requests the selected currencies from its rate provider without sending your amount.

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