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IBC 2015 Allowable Area Calculator

Jonathan Ochshorn


Directions: Enter values for occupancy classification, construction type, sprinklers, and proposed number of stories, as well as building perimeter lengths and distances from building to property lines. Press "update" button.

Values are calculated for allowable areas, heights, and numbers of stories. The site plan (Fig. 1) corresponds to the default values indicated below for a proposed 4-story, unsprinklered office building (occupancy class = B) of type III-A construction. Distances may be measured from the building to the far side of a "right-of-way" [R.O.W.], as is shown for the building perimeter facing east. In this case, the distance is 35 feet. Some occupancies require sprinklers under certain circumstances: see notes immediately below calculated values for details.

Notes and clarifications:

For more information, see my online building code handout.

site plan with yard dimensions
Fig. 1. Site plan showing yard and building dimensions.