Flat roofs on extensions, garages, dormers and outbuildings need specialist attention. We install GRP fibreglass, EPDM rubber membrane and high-performance built-up felt systems — each specified to su Serving Brentford and all surrounding areas in Hounslow.
Flat roofs on extensions, garages, dormers and outbuildings need specialist attention. We install GRP fibreglass, EPDM rubber membrane and high-performance built-up felt systems — each specified to suit the size, use and exposure of your flat roof. Every installation includes proper falls, drainage and upstand detailing.
The most common flat roof failure in Brentford is inadequate drainage. Original felt roofs from the 1960s-80s were often laid with insufficient fall — water pools, UV breaks down the membrane, and leaks follow. We install minimum 1:40 falls on every job using tapered insulation boards.
Before any new flat roof goes on in Brentford, we strip back to the deck and inspect the timber. In Brentford properties, we commonly find rotten plywood caused by years of ponding from inadequate falls. Catching this before the new membrane goes down saves a callback later.
GRP fibreglass gives a seamless, rigid surface that handles foot traffic — ideal for balconies and walkable roofs. EPDM rubber is flexible, handles movement well, and comes in single sheets that eliminate seam failures. For most Brentford extensions under 20m², GRP is our recommendation.
Victorian terraces around the High Street and Windmill Road. Post-war housing on the Syon estate. Major regeneration around Brentford Lock with modern apartment blocks. Mixed-era stock along Boston Manor Road. For flat roofing work in Brentford, this housing profile means we commonly encounter Grand Union Canal proximity creates persistent damp on properties along Brentford Lock. Victorian terrace roofs with original Welsh slate now delaminating. New-build snagging issues on regeneration ap
The streets of Brentford — including Brentford High Street, Windmill Road, Boston Manor Road — have roofing characteristics that reflect their construction era and the specific exposure conditions of Hounslow. Hounslow's proximity to the Thames creates localised humidity issues, particularly in Chiswick, Brentford and Isleworth where riverside properties face accelerated moss growth and lead oxidation. The
Flat Roofing in Brentford: £800–£6,000 depending on scope, access and materials. Free, written, no-obligation quotes. Call 0203 302 2547.
Free quotes, no call-out fees, same-day emergency service.
📞 Call Now: 0203 302 2547"Flat roof replacement on our kitchen extension — called on a weekday and they were out within days. Professional, tidy, and the price was exactly as quoted. Highly recommend."
"Slate repair matching original victorian tiles — called on a weekday and they were out within days. Professional, tidy, and the price was exactly as quoted. Highly recommend."
"Flat roof conversion from felt to grp fibreglass — called on a weekday and they were out within days. Professional, tidy, and the price was exactly as quoted. Highly recommend."
A typical single-storey rear extension flat roof in Brentford costs £1,200–£3,000 depending on size and system. Garage roofs run £800–£2,000. Larger commercial or multi-section flat roofs can be £4,000–£6,000+.
GRP fibreglass lasts 30-40 years with minimal maintenance. EPDM rubber membrane lasts 25-30 years. Traditional felt typically lasts 10-15 years. We recommend GRP or EPDM for any flat roof in Brentford — the upfront cost is recovered many times over in lifespan.
Yes — GRP fibreglass is seamless, UV-stable, impact-resistant and lasts 2-3 times longer than felt. The only advantage felt has is lower upfront cost, which is a false economy over 20+ years.
If the membrane is sound but a localised area has failed, we can patch repair. If the membrane is blistered, cracked or ponding across more than 20% of its area, full replacement is more cost-effective.
Under current Building Regulations, any flat roof replacement must include insulation to meet thermal performance standards. We install rigid insulation boards above the deck, which also creates the correct drainage falls.
The three most common causes in Brentford are: ponding water from inadequate falls, membrane failure at upstands and abutments, and blocked outlets. All three are preventable with correct specification and installation.
A typical extension flat roof takes 1-2 days. Larger projects or those requiring significant deck repairs take 2-4 days. Weather-dependent — GRP cannot be laid in rain.
Hounslow's roofing story is shaped by two forces: the Thames and Heathrow. Riverside properties in Chiswick, Brentford and Isleworth have roofing challenges driven by humidity, flood risk and the specific material requirements of their conservation areas. Properties further west in Hounslow, Heston and Feltham face the unique environmental stress of the Heathrow flight path — sustained low-frequency vibration from aircraft on approach that gradually loosens mortar joints and ridge fixings.
The Thames corridor through Hounslow creates a microclimate that makes seasonal roof maintenance essential. Winter humidity promotes moss and algae growth that is noticeably worse on north-facing pitches near the river than on equivalent roofs just a mile inland. Autumn gutter clearance is critical — the mature plane trees along Chiswick High Road, Strand-on-the-Green and Brentford High Street produce enormous volumes of leaf debris that can block an entire gutter run in a single week.
Chiswick and Brentford have seen significant property price growth, with many Victorian and Edwardian houses now valued above £1 million. In conservation areas covering much of Chiswick and Old Isleworth, roofing materials must match originals — a requirement that adds 30-60% to costs but protects both the streetscape and your property's premium value.
Flat roof installation follows a strict sequence that cannot be shortcut. Stage one: strip the existing covering and inspect the deck. Stage two: repair or replace any damaged deck timbers — rotten OSB or plywood is the most common finding on existing flat roofs. Stage three: install tapered insulation boards to create the correct drainage falls (minimum 1:40 gradient). Stage four: apply the chosen membrane system — GRP fibreglass with resin lamination, or EPDM rubber with bonded seams. Stage five: detail all upstands, drip edges and abutments. Stage six: inspect, photograph and hand over.
GRP fibreglass creates a seamless, rigid surface that handles foot traffic and resists impact — ideal for balconies, walkable roofs and areas where you need to access equipment. EPDM rubber is flexible, accommodates structural movement, and comes in single sheets up to 15m wide that eliminate seam failures. Both systems carry 25-40 year lifespans when correctly installed. We do not install traditional felt systems for new work — the lifespan is too short to justify the labour cost of installation.
All flat roof installations carry our 10-year workmanship guarantee. GRP systems additionally carry a 25-year manufacturer guarantee on the membrane when installed by an approved contractor — which we are. EPDM carries a 20-year manufacturer guarantee on the membrane. These guarantees are meaningful because both products have track records exceeding their guarantee periods.
No call-out fees. No obligation. Just an honest quote from a local Brentford roofer who turns up when they say they will.
0203 302 2547 📞 Call Now: 0203 302 2547