5' X 10' X 8'= 400 Cubic Feet10' X 10' x 8'= 800 Cubic Feet10' X 15' x 8' = 1200 Cubic Feet10' X 20' x 8' = 1600 Cubic Feet10' X 30' x 8' = 2400 Cubic Feet10' X 40' x 8' = 3200 Cubic Feet