Traditional mineral felt flat roofs have largely given way to modern, high-performance synthetic waterproofing membranes. If you are renovating a rear kitchen extension, dormer roof, or garage in South West London, two systems lead the market: EPDM rubber and GRP fibreglass.
1. EPDM Rubber Roofing (Ethylene Propylene Diene Monomer)
EPDM is a durable synthetic rubber sheet installed in single large seamless pieces.
- Seamless Installation: Cut to exact dimensions from large rolls, eliminating vulnerable seams on roofs up to 100 square metres.
- Flexibility: Remains flexible across extreme temperature swings (-40°C to +120°C), easily accommodating thermal expansion and building movement.
- Expected Lifespan: 30 to 50 years with virtually zero routine maintenance required.
2. GRP Fibreglass Roofing (Glass Reinforced Plastic)
GRP is a cold-applied liquid resin system reinforced with chopped strand glass matting, curing into a continuous, rigid, impact-resistant laminate.
- Seamless Hard Finish: Completely joint-free finish that easily forms around roof lanterns, soil pipes, and complex parapet upstands.
- Foot Traffic: Extremely hard-wearing surface ideal for flat roofs that double as accessible roof terraces or balconies.
- Aesthetics: Crisp, modern dark grey finish with matching pre-formed edge trims.
Which System Is Right for Your Home?
For standard extensions and large uncomplicated roof decks, EPDM offers unbeatable flexibility and long-term value. For complex roof shapes with skylights, parapet walls, or light foot-traffic requirements, GRP fibreglass provides a rock-solid, visually striking finish.