The 'Area of the wall' will give you the floor plan area (footprint).
You want you use 'Surface area'.
There are a few to choose from depending on what you want (i.e. with or without openings).
Try them all and see what gives the figures you expect.
As for the units you can set those in the 'Calculation Units' in the Options menu > Project Preferences > Calculation Units.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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