Secondary Roof Drainage Design

There are 3000 roof collapses a year in the.

Secondary roof drainage design.

Example of a primary secondary thru wall drainage to downspout courtesy of ernie s gutter. Secondary emergency roof drains or scuppers are required according to ipc to prevent a rainwater build up. Roof drainage is one of the fundamental considerations of building design. Roof collapses are prevented if primary and secondary drainage systems are designed properly.

Once the required rainfall data has been determined the primary and secondary roof drainage system must be sized in accordance with. P 1503 4 1 secondary emergency overflow drains or scuppers. Generally the roof system is more durable. 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.

When installing a secondary roof drainage system a licensed plumber must adhere to the following provisions issued by the board. See section 1107 for yourself. 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. P 1503 4 roof drainage.

In many cases early structures were designed primarily as a shelter from the rain their very purpose was to redirect rainfall and maintain a particular area. The drainage system shall incorporate adequate cleanouts placed in a manner that the drainage system may be readily cleaned. Otherwise the system will not adhere to the above referenced principle. Design and installation of roof drainage systems shall comply with section 1503 of this code and sections 1106 and 1108 as applicable of the international plumbing code.

In either case the discharge shall be located so that it is readily visible by building occupants. It s very short and to the point. Following these four steps you can successfully specify the correct size of horizontal and vertical drains required for any roof. Secondary drainage shall be provided through the use of sidewall scuppers or internal roof drains.

Ponding instability is avoided. Adequate drainage is an important component of a properly installed roof so installing the correct size of drains is essential. Why is roof drainage so important. Roof drainage systems tend to be given little attention until they fail.

Firstly there is an explanation in the above referenced section for where and why a secondary roof drainage system must be provided. The roof system is less susceptible to leakage. 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.