CrownPeak
EPDM & GRP Flat Roof Specialists Across Harrow
Flat roofs on Harrow extensions, garages, and dormer windows need specialist materials and installation techniques to deliver reliable waterproofing. CrownPeak Roofing installs premium EPDM rubber and GRP fibreglass flat roof systems across Harrow, providing seamless waterproofing with manufacturer-backed guarantees of up to 20 years. We also repair existing felt, asphalt, and rubber flat roofs.
Modern Flat Roof Solutions for Harrow Properties
Many Harrow properties have flat roof extensions, garages, or dormer windows covered in traditional felt that has a lifespan of just 10-15 years. When this felt fails, it causes persistent leaks and damp that damage ceilings, walls, and timbers below. We replace failing felt with modern EPDM or GRP systems that last 25-50 years.
EPDM rubber membrane is our most popular choice for Harrow flat roofs — it's a single seamless sheet with no joints to fail, resistant to UV degradation, and handles thermal movement without cracking. For areas needing a walkable finish or where aesthetics matter, we install GRP fibreglass which creates a hard, durable, completely waterproof surface.
Flat Roof Services We Provide
- EPDM rubber membrane installation
- GRP fibreglass flat roof systems
- Felt flat roof replacement
- Flat roof leak repair
- Ponding water solutions
- Flat roof insulation upgrades
- Dormer window flat roofing
- Garage flat roof replacement
- Parapet wall and upstand repair
- Green roof and balcony waterproofing
Why Choose CrownPeak in Harrow
- EPDM and GRP certified installers
- Manufacturer-backed guarantees up to 20 years
- Experienced across all Harrow property types
- Free survey and fixed-price quotes
- Insulation upgrades to reduce heating costs
- Clean, single-day installation for most jobs
Signs Your Harrow Flat Roof Needs Attention
The most obvious sign is water ingress — damp patches on the ceiling below the flat roof, peeling paint, or a musty smell. On the roof itself, look for cracks in felt, blistering, standing water that doesn't drain within 48 hours of rain (ponding), and vegetation growing in accumulated dirt.
Many flat roofs on Harrow extensions were installed using cheap felt in the 1980s-90s and are now well past their 15-year lifespan. Even if they're not actively leaking yet, deteriorated felt is just one heavy rainfall away from failure. A proactive replacement with modern EPDM or GRP is far cheaper than waiting for water damage to ceilings and timbers.
Flat Roof Replacement in Harrow — Free Survey
EPDM and GRP systems from £1,400–£3,200. Guaranteed for up to 20 years.
Flat Roof Services in Harrow — Your Questions Answered
Flat roof installation in Harrow costs £1,400–£3,200 depending on the system chosen and area covered. EPDM rubber is the most cost-effective for standard extensions. GRP fibreglass costs slightly more but offers a hard, walkable finish. We provide free measured quotes.
EPDM rubber is ideal for most Harrow flat roofs — it's cost-effective, seamless, and lasts 25-50 years. GRP fibreglass is better if you need a walkable surface (like a balcony) or want maximum durability. We'll recommend the best option for your specific situation during our free survey.
Most flat roof installations across Harrow are completed in 1-2 days for standard extensions and garages. Larger or more complex projects may take 2-3 days. We work through each stage methodically to ensure a perfect watertight finish.
Yes. We repair all types of flat roofs across Harrow including felt, EPDM, GRP, and asphalt. If the underlying decking is sound, a repair or overlay may be more cost-effective than full replacement. We'll advise honestly after inspection.
All our flat roof installations in Harrow carry manufacturer-backed guarantees of up to 20 years for EPDM and 25 years for GRP systems. We also provide a 12-month workmanship warranty and insurance-backed guarantee options.
Verified Reviews
“CrownPeak replaced the flat roof on our kitchen extension in Pinner with EPDM rubber. Clean, professional installation completed in one day. No more leaks, no more worry. The 20-year guarantee gives us complete confidence.”
“Our dormer window flat roof in Stanmore was leaking badly through old felt. CrownPeak installed GRP fibreglass — it looks fantastic and is completely watertight. They also improved the insulation which has made the bedroom noticeably warmer.”
“Had three quotes for our garage flat roof in Kenton. CrownPeak were the most professional — they explained the options clearly, recommended EPDM, and installed it perfectly in half a day. Price was competitive and the quality is outstanding.”
Areas We Cover in Harrow
We serve every neighbourhood across Harrow and surrounding areas. No matter where you are in the HA1–HA9 postcode areas, our local team can reach you quickly.