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Preformed shape for use with downpipes drainage holes on flat roofs. Manufactured with perforated flange to improve bond to waterproofing membrane. Flexible, tough EPDM shape is inserted into drainage hole and bonded and / or mechanically fixed to the waterproofing membrane in a sandwich application.

Outlet shape is placed onto the rubber waterproofing and bonded using adhesive. Adhesive will ooze through the perforations to achieve an over-and-under bond. A patch of waterproofing is installed above the outlet flange and fully bonded completely over the top to ensure area is watertight. Drainage outlet is protected by having additional layer and fully sealed.

A round leaf guard should be inserted into top of hole once installed. Always prime both the outlet shape and the waterproofing membrane before installation.

General information



Holes throughout the face, waterproof seal


Ethylene propylene diene monomer rubber


250 x 406 x 183 x 183 x 192 mm

Uniclass 2015
Gravity rainwater outlets (Pr_65_50_35_37)Primary
Digital objects
PlatformCompatibleVersionCertified to
- 1 2.1
Revit 2017 1 2.1
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