LarryBC

Thanks, TeaTime. That article answered my question. Measurements are from the main layer of external walls rather than the surface. In the old version I have, there's no way to change the setting to the actual inner surfaces as shown in the article. If I draw the same 100' x 50' outline using interior walls instead of exterior, the area correctly displays as 5000 sq. ft. Thanks to JiAngelo as well.

I'm using a very old edition of Chief Architect (X1 from 2007). After starting to suspect some dimension problems, I drew a plan 100' x 50' containing no interior dividing walls. Outer walls are 1' thick. Since wall dimensions are defaulted to surfaces, I expected Living Area to show as 5000 sq. ft. However, it shows 5163 sq. ft. Don't know whether there's a setting I may have somehow overlooked, there's a bug in the program or it just aged out of reliability. Thanks for your ideas for a possible solution.