Home > Instructions and How To's > How to Properly Size a Cupola
The old "rule of thumb" is:
'For every foot of building width, you should have at least 1.25 inches of cupola'
So, measure the width of your building and times that by 1.25.

This guideline
is a minimum rule of thumb to get a cupola into proportion. Structures two stories and higher may require one size up, or 1.5" per foot of roof.