Construction
Room Volume Calculator
Calculate the volume of a rectangular room from length, width and height.
The result is the total space inside the room in cubic metres, which is the floor area multiplied by the height.
Formula
Room volume = length multiplied by width multiplied by height.
How it works
Multiply the three room dimensions to get cubic volume. Volume matters for heating, cooling, ventilation and acoustics, since a tall room needs more air handling than a low room of the same floor area.
Worked example
For example, 5 m × 4 m × 3 m = 60.00 cubic metres.
FAQs
What if the room is L-shaped?
Split it into rectangles, calculate each volume, and add them together.
Do I use internal dimensions?
Yes, measure inside wall to inside wall for usable room volume.
Why does volume matter?
Heating, cooling and fresh-air systems are sized on volume, not floor area alone.
Rough estimate only — consult a licensed professional for structural work before building.
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