Flat roofs on Portslade extensions, garages and outbuildings require specification appropriate to local conditions. We install GRP fibreglass and EPDM rubber flat roofing to a standard that lasts 30-40 years in this climate.
Nail sickness endemic on 1960s-70s concrete tile estates. The flat roofs on Portslade's extensions, garages and outbuildings require the right material specification for local conditions. We install GRP as our first choice in exposed positions.
Coastal but more sheltered than open Brighton seafront due to the harbour arm and industrial port screening. Higher particulate pollution from the port area deposits on roof surfaces, accelerating biological growth and tile degradation. Correct fall and drainage specification is critical in Portslade's rainfall pattern. We survey the existing structure, assess drainage routes, and specify falls that clear the roof surface within 24 hours of rainfall stopping.
We always strip to the deck before installation. Common findings on Portslade properties: saturated OSB or plywood deck from years of felt failure; joist rot from sustained moisture; inadequate insulation. We document all findings before quoting for extra work — never proceed without your agreement.
A GRP flat roof in Portslade requires minimal maintenance — an annual inspection and clearing of any debris from outlets. EPDM requires lap joint inspection every 2-3 years in East Sussex conditions. We carry out free annual inspections for all flat roofing customers for the first 5 years after installation.
| GRP fibreglass (per sqm installed) | £70 - £90 |
| EPDM rubber (per sqm installed) | £55 - £75 |
| Kitchen extension (20-25 sqm) | £1,400 - £2,250 |
| Garage (20-30 sqm) | £1,400 - £2,700 |
| Larger area (40-60 sqm) | £2,800 - £5,400 |
“Old felt roof on the extension had been leaking for two years. GRP installed in a day and a half. Looks completely different and I have no doubt it will outlast everything else on the property.”
“Replaced the garage felt with GRP. Quick, tidy and they found some deck rot I wasn't aware of — fixed it and showed me before proceeding. Honest job.”
“Third flat roof replacement in 30 years on the same extension. Went with GRP this time on their advice. Should be the last time I ever need to do it.”
Victorian and Edwardian terraces in Portslade Village, 1950s-70s post-war estates in South Portslade. Clay tile in the village, concrete interlocking on post-war estates now 50-70 years old..
Coastal but partially sheltered by the harbour arm. Higher industrial particulate from port activity deposits on roof surfaces..
Industrial particulate from the port settles on north-facing slopes, accelerating lichen and moss colonisation faster than equivalent coastal towns..
Pricing note: Post-war concrete tile is now at or near end of design life on many Portslade properties — survey essential before repair commitment..
Every job follows the same clear process — no surprises, no hidden costs, full communication throughout.
We inspect the existing membrane, check drainage falls, assess the deck condition and identify any structural issues before quoting.
All existing felt or membrane stripped. Deck inspected thoroughly — any rot or saturation documented and quoted for before work proceeds.
Deck repaired or replaced where needed. Any drainage issues corrected. Falls assessed and improved where possible.
New membrane installed to manufacturer specification. GRP: full lamination across the entire deck as a single membrane. All upstands, outlets and penetrations correctly detailed.
10-year written workmanship guarantee issued. Free annual inspection for the first 5 years after installation.
GRP fibreglass is our recommendation for most Portslade properties. It forms a seamless, jointless membrane with no lap joints to fail, resists UV well, and has an expected life of 30-40 years. EPDM is suitable for sheltered positions. Traditional felt is not recommended for East Sussex conditions.
GRP fibreglass is £70-90 per sqm installed. A typical kitchen extension (20-25 sqm) costs £1,400-£2,250. A double garage (40 sqm) costs £2,800-£3,600. All prices include stripping the old felt and debris disposal.
GRP fibreglass correctly installed lasts 30-40 years in East Sussex conditions. EPDM lasts 20-30 years. Traditional felt lasts 8-12 years. The significant lifespan difference justifies the higher upfront cost of GRP for most customers.
Replacing a flat roof with the same material and specification is permitted development. Changing the roof type (e.g. adding a raised parapet or changing the drainage system significantly) may require planning approval. We advise on this during the free survey.
Yes — this is the most common flat roofing job we carry out. We strip all existing felt, inspect and repair the deck if needed, and install a GRP system directly over the existing structure in most cases.
10-year written workmanship guarantee on all GRP and EPDM installations. The GRP material itself carries a manufacturer guarantee of 25 years.
We cover Portslade and the surrounding area including Hove, Shoreham, Brighton. Call 01273 973 996 to arrange a free survey.
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