Flat Roofs
Flat roofs are roofs with little or no slope. They are common on commercial and industrial buildings and, in some regions, on residential architecture. Though called "flat," they have a slight slope to direct water toward drains.
Membrane systems[edit]
Because flat roofs do not shed water as quickly as pitched roofs, they rely on continuous waterproof membranes:
- EPDM — a synthetic rubber membrane
- TPO — a heat-weldable thermoplastic membrane, often white for reflectivity
- PVC — a durable thermoplastic membrane
- Modified bitumen — asphalt-based rolled roofing
- Built-up roofing (BUR) — alternating layers of bitumen and reinforcing fabric
Considerations[edit]
Flat roofs need reliable drainage, regular inspection, and careful flashing around penetrations to prevent ponding water and leaks.