Flat Roofing in Portsmouth & Hampshire
EPDM, GRP and felt flat roofing for extensions, garages and dormers. 20-year material guarantees.
Failing flat roofs are the single biggest source of leaks in UK homes. Most of the trouble comes from old felt installs from the 1980s and 90s that were good for 10-15 years and have now had 30. Modern EPDM rubber and GRP fibreglass are completely different products — properly fitted, both routinely last 25-50 years with no maintenance. We install all three systems across Portsmouth and Hampshire on extensions, garages, dormers, porches and bay windows, and we'll tell you honestly which one suits your roof. Most homeowners don't know the difference between EPDM, GRP and felt; the cheapest option is rarely the right one and the most expensive isn't always the best. Where the existing decking is sound we re-use it; where it isn't, we strip and replace. Falls are checked or rebuilt so water actually leaves the roof. Free written quote within 48 hours, with the system options compared in plain English.
What we install
EPDM rubber flat roofing
One-piece rubber membrane, no seams on most domestic roofs. Lifespan 50+ years. Our default recommendation for most flat roofs.
GRP fibreglass flat roofing
Hand-laid fibreglass with a hard, walkable finish. Lifespan 25-30 years. Best for smaller roofs and complex shapes.
Felt flat roofing
Three-layer torch-on felt. The budget option, 10-15 year lifespan. Honest answer: rarely worth it any more for a permanent roof.
Single-ply membrane systems
PVC and TPO single-ply for larger commercial and outbuilding roofs where EPDM isn't practical.
Extension roofs
Single-storey kitchen, dining and bedroom extensions. Insulated decks, edge trims, and proper integration with the existing roof.
Garage roofs
Detached and integral garage roofs. Most done in a single day in EPDM with new edge trims and gutter integration.
Dormer roofs
Flat-roof dormers re-covered in EPDM with proper lead flashings into the main roof. Common job on Portsmouth Victorian terraces.
Porch roofs
Small porch and bay window roofs in GRP or EPDM. Often a half-day job, scaffolding rarely needed.
Flat roof repairs and patch work
Honest answer first — if a repair will only buy you 12 months on a roof that's nearly done, we'll say so.
How it works
Free Inspection
We come out, climb up, take photos and explain what we find in plain English. No charge, no follow-up sales calls.
Written Quote
Itemised, fixed-price quote within 48 hours. Materials specified by name. No hidden extras on the day.
Scheduled Work
Agreed date booked, fully scaffolded where needed, all materials delivered to site before we start.
Guarantee in Writing
10-year workmanship guarantee, site swept clean, after-photos sent before we collect payment.
EPDM vs GRP vs Felt — at a glance
| EPDM Rubber | GRP Fibreglass | Felt | |
|---|---|---|---|
| Lifespan | 50+ years | 25-30 years | 10-15 years |
| Cost (£/m²) | £90-£130 | £100-£140 | £60-£90 |
| Maintenance | Effectively none | Occasional re-coat | Annual checks |
| Best for | Most domestic flat roofs | Small/complex shapes | Tight-budget outbuildings |
Flat roofing pricing
Honest indicative pricing. Real quotes depend on access and condition. Free written quote within 48 hours.
Small flat roof (up to 15m²)
From £1,500
Garage or porch, typical range £1,500-£3,000
Medium flat roof (15-30m²)
From £2,500
Single-storey extension, typical range £2,500-£5,500
Large flat roof (30m²+)
From £4,500
Larger extensions, typical range £4,500-£9,000+
What affects the price
- System chosen — EPDM premium, GRP mid, felt budget
- Insulation specification (cold deck, warm deck, inverted)
- Edging, trims and any lead flashings into adjoining roofs
- Removal and disposal of the existing roof covering
- Roof lights, lanterns or openings to be re-trimmed
All prices indicative. Free written quote within 48 hours.
What our flat roofing customers say
"New flat roof on the garage in EPDM. In and out in two days, perfect job, fair price. Has not leaked through three winters."
— Mark T., Lee-on-the-Solent
"Replaced our extension roof in EPDM after years of patching. Wish we'd done it sooner — proper job, 20-year guarantee."
— Helen R., Park Gate
"Old felt roof on the dormer was on its last legs. Re-covered in GRP, neat lead detail back into the main roof. Top quality."
— Steve A., Hayling Island
Areas we cover for flat roofing
We provide flat roofing across Portsmouth, Hampshire and within 40 miles of our Portsmouth base.
Frequently asked questions
Flat Roofing questions we hear most often. Don't see yours? Call us.
For most domestic flat roofs in Hampshire, EPDM is our default — one-piece, no seams, 50-year lifespan, weathers UK rain and UV well. GRP is the answer for smaller roofs and detailed shapes. Felt is the budget option but rarely the smart spend.
You might also need
Roof Repairs
Slipped tiles, leaks, storm damage and isolated faults — fixed properly the first time.
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Re-Roofing
Complete roof replacements built to last 50+ years. Premium materials, 10-year workmanship guarantee.
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Emergency Roof Repairs
Storm damage, active leaks, fallen trees. Same-day make-safe across Hampshire.
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