Primary And Secondary Roof Drains

The primary system consists of roof drains piping serving those drains and the discharge method used either surface or gravity drainage or pumped drainage.

Primary and secondary roof drains.

Where should the secondary drainage be discharged. If discharge is witnessed it s a telltale sign that the primary roof drain may be clogged. If the sump is shallower than 2 it will be full of standing water which may freeze and damage the drain and the adjacent roofing. 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 to pour over top of outlet box if primary clogs. The upc also allows for secondary and primary drainage to be combined provided the rainfall rate utilized is doubled and that the secondary drainage ties into the primary drain downstream of the last horizontal offset. A secondary drain placed in a sump will start working as soon as water reaches the top of the standpipe. The froet drain froet industries llc america s most innovative roof drain manufacturer presents the froet drain roof drain primary and secondary roof drain in one engineered fixture.

The patented froet drain is an innovative drain product created to solve the dual drain requirement for overflow protection. Where primary and secondary roof drains are manufactured as a single assembly the inlet and outlet for each drain shall be independent. 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. If the sump is 2 or deeper the secondary drain shall serve as the primary drain totally defeating its purpose.