Because of the limited fall available for the installation of a building storm drainage system, a fall of 1/8 inch per foot is used. If the maximum rainfall is 4 inches per hour and the roof area is 27,350 square feet, the Code required minimum pipe size for the building storm sewer is ____ inches.

Because of the limited fall available for the installation of a building storm drainage system, a fall of 1/8 inch per foot is used. If the maximum rainfall is 4 inches per hour and the roof area is 27,350 square feet, the Code required minimum pipe size for the building storm sewer is ____ inches.