EPDM vs GRP Flat Roofing: Which Is Right?

EPDM and GRP are both popular flat roofing systems. The right option depends on the roof shape, details, installer skill and how the roof will be used.

By Max, Surrey Roofing & Windows Ltd | Updated May 2026

EPDM and GRP are both popular flat roofing systems. The right option depends on the roof shape, details, installer skill and how the roof will be used.

EPDM rubber roofing

EPDM is flexible and works well on many simple flat roofs. It can be a good option where movement is expected, but details around edges, outlets and penetrations still need careful workmanship.

GRP fibreglass roofing

GRP creates a hard, seamless surface and can look very neat when installed correctly. It is especially dependent on preparation, weather conditions and correct detailing.

How to choose

Ask the roofer why they recommend one system over another for your exact roof. The answer should mention deck condition, falls, edges, outlets, rooflights and maintenance.

Useful next steps

If you need roofing advice for a Surrey property, start with the relevant service page: roof repairs, emergency roof repairs, flat roofing, roof replacement or roof surveys. We also cover towns including Weybridge, Cobham, Woking, Guildford and Epsom.

FAQs

Is EPDM cheaper than GRP?+
Often it can be, but the total cost depends on roof size, deck condition and detailing rather than membrane alone.
Can GRP be used around roof lanterns?+
Yes, when the upstands and trims are formed correctly and compatible details are used.
Need a Surrey roofing quote?Call 07565 812922 or use the free quote form. For active leaks, call now so we can triage the issue quickly.