Secondary Roof Drainage For Exterior Leaders

Better to design appropriate drainage assemblies and address incipient concerns now than to chase.

Secondary roof drainage for exterior leaders.

A good rule to follow is to provide two roof drains for a total roof area less than 10 000 square feet. Secondary emergency roof drains or scuppers are required according to ipc to prevent a rainwater build up. See section 1107 for yourself. The better choice if it can be accommodated is one of the first two methods where overflow at the exterior of the building roof is provided without the need for secondary drainage piping.

Secondary drainage shall be provided through the use of sidewall scuppers or internal roof drains. Once the drainage system is determined the designer must ensure positive drainage by correctly positioning the roof drains. Scuppers shall be sized to prevent the depth of ponding water from exceeding that for which the roof was designed as determined by section 1101 7 scuppers shall have an opening dimension of not less than 4 inches 102 mm. Example of a primary secondary thru wall drainage to downspout courtesy of ernie s gutter.

And vent caps protect the roof leaders and vent stacks from vandalism pro hibiting foreign objects being either carelessly or maliciously placed in the. Where scuppers are used for primary roof drainage or for secondary emergency overflow roof drainage or both the quantity size location and inlet elevation of the scuppers shall be chosen to prevent the depth of ponding water on the roof from exceeding the maximum water depth that the roof was designed for as determined by section 1611 1 of the international building code. Firstly there is an explanation in the above referenced section for where and why a secondary roof drainage system must be provided. Once the required rainfall data has been determined the primary and secondary roof drainage system must be sized in accordance with.

Roof drainage systems tend to be given little attention until they fail. The limiting factor for this method is the ability to locate the primary drainage point within close enough proximity to the exterior of the building to. A roof surface with a slope of inch per foot 0 0208 rad or greater towards points of free drainage is not a susceptible bay. In either case the discharge shall be located so that it is readily visible by building occupants.

Secondary emergency roof drain systems shall be sized in accordance with section 1106 based on the rainfall rate for which the primary system is sized. Section 1611 2 ponding instability states. The secondary roof drains can be of two types roof drains with an independent piping system or roof drains that combine with the primary roof drainage piping which will require an increase in piping size. In those systems.

It s very short and to the point. On which water is impounded in whole or in part and the secondary drainage system is functional but the primary drainage system is blocked. Considering the damage water can do when allowed to pond on roofs and overflow from gutters it is clear that ignoring roof drainage issues can lead to urgent problems.