Prior to the 1994 upc the only mention of secondary roof drains is a listing of the materials to be utilized for over flow drains in the 1994 upc rainwater systems was included as appendix d to the code.
Secondary roof drain code requirements.
This is completed using a plumbing calculation.
The uniform plumbing code followed a similar path to incorporating secondary drainage requirements.
Using ibc 2009 or ibc 2012 it could be inter preted the addition of secondary drainage may be required during reroofing this was not the intent of the 2009 code change.
Firstly there is an explanation in the above referenced section for where and why a secondary roof drainage system must be provided.
It s very short and to the point.
The minimum slope the code allows is in 12 in.
Secondary drainage was not required with ibc s previous editions.
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.
When a secondary roof drainage system is installed it shall discharge independent of the primary building storm system and shall terminate a minimum of 18 above grade in an area that will be visible to the people who occupy the building.
The rationale for not requiring secondary drainage is that if positive drainage is provided that is adequate to drain the roof.
Where roof drains are required secondary emergency overflow roof drains or scuppers shall be provided where the roof perimeter construction.
Part a d1 1 d notes that.
We would like to show you a description here but the site won t allow us.
This system shall be compliant with all federal state and local codes.
Ibc s secondary roof drainage requirement first was added in ibc 2009.
See section 1107 for yourself.
1511 1 roof assemblies and rooftop structures general.
Secondary emergency roof drains or scuppers are required according to ipc to prevent a rainwater build up.
Roof system provides for positive drainage.
If they are used for secondary drainage then they should be a minimum of 2 inches above the roof level and a maximum of 4 inches above the roof level.
Once the number of required drains for the area is determined the size of the drain inserts and plumbing should be established.
