An overflow drainage system will be designed to function independently of the primary system to drain water from the roof.
Secondary roof scupper drains.
By the 1997 edition of the upc section 1101 11 2 had been added that completely prescribed where and how secondary roof drainage was to be provided.
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.
Section 1503 4 2 scuppers when scuppers are used for secondary emergency overflow roof drainage the quantity size location and inlet elevation of the scuppers shall be sized to prevent the depth of ponding water from exceeding that for which the roof was designed as determined by section 1611 1.
Scuppers can be installed to carry water into gutters or directly into downspouts through conductor heads.
It s very short and to the point.
Scuppers will play one of two roles in a roof system.
Secondary emergency roof drains or scuppers are required according to ipc to prevent a rainwater build up.
Scuppers are used to provide an outlet through parapet walls or gravel stops on flat and built up roofs to allow drainage of excess water.
Firstly there is an explanation in the above referenced section for where and why a secondary roof drainage system must be provided.
A the maximum drain down time does not exceed 24 h b the roof structure is designed to carry the load of the stored water c one or more scuppers are installed not more than 30 m apart along the perimeter of the building so that i the scuppers are designed to handle at least 200 of the 15 minute rainfall intensity and.
The secondary roof drainage system can be of two methods roof scuppers open sides of parapet walls or secondary roof drains.
Scuppers shall not have an opening dimension of less than 4 inches.
When scuppers are used for secondary emergency overflow roof drainage the quantity size location and inlet elevation of the scuppers shall be sized to prevent the depth of ponding water from exceeding that for which the roof was designed as determined by section 1611 1.
See section 1107 for yourself.
Where roof drains are required secondary emergency overflow roof drains or scuppers shall be provided where the roof perimeter construction extends above the roof in such a manner that water will be entrapped if the primary drains allow buildup for any reason.
They can be used in conjunction with gutters and downspouts to divert the flow to the desired location.
They will either be a part of the primary drainage system or they will be a part of the secondary overflow drainage system a primary drainage system is designed to remove water from the roof as quickly as possible.
