Flat Roof Parapet Height

The parapet height may have to have a minimum height if it is part of a fire rated assembly between units depending upon the use and classification of the structure.

Flat roof parapet height. Height of roofing at wall. Minimum of 12 to top of parapet. 2015 ibc code commentary. It is used at a single ply roof membrane sloped per foot to a gutter like on the bainbridge residence that we designed and built above.

Unfortunately many buildings get close to this height without quite meeting the height required by osha to provide fall protection. Like any roof with batt. Do not lap tpo over top of parapet unless required by unique construction conditions. The height of the building is calculated to the highest roof element not the parapet or mechanical protrusions vents chase etc.

However when a roof slopes down toward an exterior wall and parapet with a slope greater than 2 12 further analysis is required to determine if a taller parapet is necessary. The assembly is straight forward but what complicates matters is that the roof needs to be vented. At the highest point of the sloped roof the parapet is about 10 tall at the lowest point the parapet is about 14 tall. The minimum height of a parapet wall above the roof surface is 30 inches.

Measuring a flat roof on a typical commercial building with a parapet can be arduous and complicated. The parapet itself is standard wood framing with an applied siding in this case t g 1 4 cedar. First of all commercial and multi unit residential buildings are a lot bigger than single family homes in most cases. Also there may be several roof penetrations and other obstacles that should be factored into the measurement.