EPDM and GRP are the two modern flat roof systems most Oxfordshire homeowners are choosing between when felt fails. Both will out-last torch-on felt by a decade or more, but they behave very differently in installation, repair and long-term performance. This guide is the honest version — what we'd tell a friend asking which to fit on their extension.
Which lasts longer, EPDM or GRP?
EPDM typically lasts 30–50 years if undisturbed. GRP usually 25–30 years. Both significantly out-last traditional felt.
EPDM is usually £20–£40/m² cheaper supplied and fitted. The gap narrows on small, fiddly roofs where GRP's neater detailing saves labour.
Can I walk on a GRP roof?
Yes — GRP is fully walkable. EPDM is not designed for regular foot traffic and will scuff.
Which is better for a Velux skylight?
GRP — the resin bonds directly to the upstand for a neat, fully sealed detail. EPDM relies on a trim and adhesive bond around the upstand.
Evans Roofing & Maintenance Ltd, Witney, Oxfordshire. Call 07960 482233 for a free written quote.