Mean Roof Height Defined

To the deck line of a mansard roof.

Mean roof height defined.

Roof height is from bottom of tires to the top of the highest exterior point on the house including any protrusions. So why is mean roof height even important and why is it even listed on the plans. The user can override this value which will alter the pressure but when calculating the windward pressure the original story heights above ground are still used. So why is mean roof height even important and why is it even listed on the plans.

Per asce 7 the mean roof height h is defined as the average of the roof eave height and the height to the highest point on the roof surface except that for roof angles of less than or equal to 10 the mean roof height is permitted to be taken as the roof eave height. In the wind load definition there is a property for mean roof height which is taken as the top story height be default. Roof height mean the elevation located at a point two thirds 2 3 of the distance between the bottom of the roof to the roof peak as measured from the eave elevation. And to the mean height between eaves and ridges for gable hip and gambrel roofs.

Roof pitch refers to the amount of rise a roof has compared to the horizontal measurement of the roof called the run. Enviro buildings modular building 325 payson ave quincy il 62301 tel. Z velocity pressure evaluated at any height z q h velocity pressure evaluated at the mean roof height h k z velocity pressure exposure coefficient defined in section 30 3 1 and given in table 30 3 1 evaluated at any height z only used for part 3 h 60 windward pressures. Per asce 7 the mean roof height h is defined as the average of the roof eave height and the height to the highest point on the roof surface except that for roof angles of less than or equal to 10 the mean roof height is permitted to be taken as the roof eave height.

The mean roof height would be the average of 12 plus 22 67 or 17 33 as shown on the building plans. To see how pitch impacts the look of a garage and changes cost click the design center button on our pole barn kits page. 217 222 5453 or 1. Building height means the vertical distance from the grade level at the main entrance to the top of the parapet that comprises the majority of the perimeter of the building for a flat roof.