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Roofing

Roofing Membrane

A continuous waterproof sheet applied to low-slope or flat roofs, including TPO, EPDM, and modified bitumen systems.

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In the Field

Low-slope membrane roofing is extremely sensitive to installation quality — seam welding (for TPO), adhesive coverage (for EPDM), and edge detailing determine whether it leaks. Ponding water is a failure mode; ensure adequate slope to drains (minimum 1/4 inch per foot).

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Rule of Thumb

Low-slope roofs must maintain a minimum 1/4 inch per foot slope to drains. Any roof that ponds water (standing water after 48 hours) is a defective design or installation and will fail prematurely.