>Cat here...... Also look at 8 sided structures they give the most space for the least amount of roof and foundation! Very cost effective as well as labor saving! A circle is better. 100ft of wall could be used to make a square 25 * 25 = 625 sq ft. Or 100/(2*3.14)= 15.9ft radius circle = 796 sq ft. I figure an octogon gives you 754 sq ft