★★★★★ 5.0 · 202 Google reviews Fully insured · Family run · 24hr callout
★★★★★ 5.0 · 202 Google reviews

Flat Roofs in Windsor & Berkshire

Flat roof installation, replacement and repair across Windsor, Berkshire and South West London: built-up felt, GRP fibreglass and EPDM rubber on properly prepared decks. Free written quotes, and a 24hr callout if your flat roof has failed suddenly.

Fully insured roofing company
5.0 rated · 202 Google reviews
Family run & owner led
24hr emergency callout
Free written quotes
Systems explained

Three Flat Roof Systems, One Honest Recommendation

There is no single best flat roof covering, only the right one for your roof's shape, use and budget. Here is how the three systems we install compare.

Built-Up Felt (Three Layer)

Torch-applied felt in three bonded layers: vapour barrier, underlay and mineral cap sheet. Proven over decades, cost-effective and easy to detail around upstands and outlets. This is the system we used on our recent Kingston flat roof rebuild.

GRP Fibreglass

Resin and glass matting laid wet and cured into a single seamless skin, finished with a topcoat. No joints to fail, very tough underfoot and crisp around complex details, so it suits balconies, bays and roofs with lots of edges.

EPDM Rubber

A single sheet of synthetic rubber bonded to the deck in one piece, so a simple rectangular garage or extension roof can be covered with barely a joint on it. Flexible in heat and cold, and quick to install.

The part you don't see

A Flat Roof Is Only as Good as Its Deck

Most flat roof failures we see were not caused by the covering. They were caused by laying a new covering over a deck that was already soft, rotten or sagging. The boards move, the new surface splits and the leak is back within a couple of winters.

So we check the deck first, every time. Where it has failed, we strip it back and lay new plywood decking with the falls set correctly so water runs to the outlet instead of ponding. Only then does the new covering go down.

We build and repair flat roofs on:

  • Garages, the classic failing felt roof on homes across Berkshire and South West London
  • Extensions, including junctions and upstands where the flat roof meets the house wall
  • Dormers, small roofs with a big job to do, detailed to work with the pitched roof around them
New plywood deck and built-up felt flat roof by Seal Pro Roofing in Kingston upon Thames
Recent flat roof

Proof: Our Kingston upon Thames Flat Roof

A complete flat roof rebuild in Kingston upon Thames: the old covering and failed boards stripped off, a new plywood deck laid, then a built-up three-layer felt system torched on over the top. Every photo below is from that job.

Free written quote

Get Your Flat Roof Priced Properly

Tell us about the roof, garage, extension or dormer, and we will arrange a free inspection and written quote covering the right system for it. Prefer to talk first? Call either number, any time.

Get Your Free Roofing Quote

Tell us about the job, we usually reply within the hour.

No spam, no obligation. We only use your details to contact you about your quote.

Prefer to talk? Speak to Cornelius on 07777 735785 or 01753 415 442

FAQs

Flat Roof Questions, Answered

It depends on the roof. Built-up three-layer felt is a proven, cost-effective choice for garages and extensions, and is what we used on our recent Kingston flat roof. GRP fibreglass gives a seamless, hard-wearing finish that suits roofs with upstands and detail. EPDM rubber is a single sheet with very few joints, ideal for simple rectangular roofs. We recommend the right system for your roof in a free written quote rather than pushing one product.
We check the deck before quoting. Laying a new covering over soft, rotten or sagging boards wastes your money because the movement underneath will crack or split the new surface. Where the deck has failed we replace it with new plywood, exactly as we did on the Kingston flat roof, so the covering has a solid, flat base.
Flat roofs are never truly flat: they should have a slight fall towards the outlet or gutter. Ponding usually means the deck has sagged or the falls were built wrong in the first place. When we rebuild a flat roof we set the falls correctly so water drains rather than sitting on the surface.
Small blisters, splits and failed joints can often be repaired if the deck underneath is dry and sound. If water has been getting into the deck for a while, or the covering has failed in several places, replacement is usually the honest answer. We inspect first and put our recommendation in a free written quote with photos.
Yes. Every flat roof we install is covered by our company workmanship guarantee and we are fully insured. If anything is not right with our work, we come back and put it right.
Reviews

What Homeowners Say About Working With Us

★★★★★

"Seal Pro Roofing did a superb job on our roof replacement. They were punctual, tidy and kept us informed throughout. The workmanship was excellent and the price was fair. Very impressed with their customer service and would happily use them again in future."

Justin Butler Google review
★★★★★

"Seal Pro Roofing delivered a great service. The team were knowledgeable and worked carefully to ensure everything was done properly. The roof looks solid and well finished. Very happy with the professionalism shown."

Victoria Harris Google review
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Free written quotes. 24hr emergency callout. A local team rated 5.0 by 202 homeowners.

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