Flat and low-slope roofs need a fundamentally different approach than a pitched roof - water sits and moves slowly rather than running straight off, so the membrane itself has to be watertight, not just water-shedding. On the many flat-roofed homes, additions, and modern infill builds across Greater Vancouver, single-ply membranes like TPO and EPDM are a clean, reliable answer.
TPO is a heat-welded thermoplastic with a reflective white surface that keeps a roof cooler and suits low-slope sections that bake in summer. EPDM is a tough synthetic rubber that stays flexible through our wet, cool winters. Both go down in large sheets with far fewer seams than older systems, and every seam is welded or bonded rather than relying on adhesive tape alone.
Our coastal rain makes the drainage details decisive. We build in proper slope to the drains and scuppers, detail every parapet, curb, and penetration, and tie the membrane cleanly into walls and skylights so standing water has nowhere to sit. Done right, a single-ply flat roof gives you decades of low-maintenance protection over living space, a garage, or a deck - and a tidy surface that will not trap the moss a textured roof invites.