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Wall area = pi*d*h = 31.4 square feet. Each course will be about 15' 6" long. You may want to finetune the radius to get an exact number of bricks with the mortar width you want rather than cutting bricks. For the floor, you will need to cut bricks, have gaps, or have bricks extending beneath the wall, so the theoretical area of 19.6 square feet may not be a very good guide to brick use. RD  


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