Flat roofs aren't truly flat — they're 1/4 inch per foot minimum slope — and they fail almost exclusively at seams and flashings. The whole job is in getting those details right. This page covers flat and low-slope roofing on homes: porch roofs, additions, dormers, and full flat residential roofs. Own a retail, office, warehouse, or multi-family building? See our commercial roofing page — same membranes, but different loads, drainage, and maintenance realities.
TPO vs EPDM — which one for your roof
TPO is white, heat-reflective, lower cooling cost in summer, and seams are heat-welded for the strongest watertight bond available. EPDM is the classic black rubber roof — slightly cheaper, proven longevity, seams are taped. For residential porch and addition roofs in our service area we lean TPO; for larger commercial flat we still install plenty of EPDM.
When You Actually Need This
- Flat porch roof leaking at the seam or against the house
- Older built-up tar roof at end of life
- Addition with a low-slope section
- Mansard, dormer, or kick-out roof needing replacement
