Completed grey flat roof with a lantern on a brick extension

Rated 5 stars on GoogleCo Operate Roofing Ltd · London and Surrey

Flat roofing Walthamstow

Flat roofing Walthamstow in EPDM rubber, GRP fibreglass and felt. Get a free survey and written quote for your extension, garage or porch roof in London and Surrey.

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Free survey and written quote
10-year guarantee on new roofs
Fully insured

10+Years experience

200+Projects completed

5.0Google rating

10yrWork guarantee

24/7Emergency callout

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Expert Roofer VerifiedCompany checks published on our member profile →

Fully insuredPublic liability cover on every job

10-year guaranteeOn new roofs. 12 months on repairs →

Start with the deck and drainage

A flat roof needs a sound deck, correctly formed falls and clear outlets. A new covering over a weak base leaves the real problem underneath. Your survey checks the existing roof, edges, wall junctions and the route rainwater takes off the roof.

EPDM, GRP or felt

EPDM is a rubber membrane. GRP uses a reinforced fibreglass system. Felt uses bonded layers with sealed laps. We explain the covering and roof details in your quote, including the treatment around rooflights, pipes and adjoining walls.

Details around the edges matter

The upstand at the wall, rooflight kerb and drip edge all need to work with the main covering. Our gallery shows an extension roof with a lantern, new decking and completed felt roofs. These are our own job photographs.

Build a dependable flat roof detail

Map the water route. Identify the highest and lowest parts of your roof. The outlet position helps explain why water collects in particular places.
Open the existing layers. Removing failed waterproofing exposes the deck surface. Soft boards and trapped moisture need resolving before a replacement membrane is fitted.
Prepare a suitable base. Deck joints and edge supports must suit the chosen system. Uneven transitions transfer weaknesses into the waterproofing above them.
Install the selected covering. Each system has its own bonding and joint details. Work around penetrations needs the same preparation as the open roof area.
Complete the perimeter. Edges need a clear drip into the drainage below. Wall upstands and outlets must finish without pockets that hold rainwater.

Look for changes in the surface

Blisters lifting a felt surface
Cracks beside a rooflight kerb
Ponding that remains after surrounding areas dry
Soft patches beneath the covering

Compare flat roof specifications

EPDM rubber membrane. Flexible sheets reduce the number of joints across open areas. Pipes, corners and upstands still need purpose-made waterproof details.
GRP fibreglass finish. A reinforced resin covering forms a continuous surface over suitable decking. Preparation and curing conditions are central to the finished result.
Layered felt covering. Overlapping layers provide the waterproof build-up. Laps must shed water in the right direction and remain secure at the perimeter.
Covering with deck renewal. Replacing weakened decking gives the new finish a stable foundation. Specify the affected boards rather than hiding them under another layer.

How long it takes

A modest flat roof can be completed over a short run of suitable working days. Deck replacement, multiple rooflights and changes to drainage extend the programme. Dry conditions are essential for preparation and bonding. Resin systems also need their specified curing conditions, so the weather forecast shapes when each stage proceeds.

What affects the price

Area and number of roof sections
Existing layers requiring removal
Deck repairs beneath the membrane
Quantity of outlets and raised details

Ask for a free flat roof quote that identifies the covering and the preparation beneath it. Get your free quote.

Looking after it afterwards

Arrange debris clearance before leaves gather around the outlet. Do not use an ordinary flat roof as a terrace or a storage platform. Sharp feet on ladders, furniture and plant pots damage waterproof surfaces. If another trade needs access, explain the roof system first and agree how the covering will be protected.

Our own roofing work

A closer look at our roofing work

Photographs from Co Operate Roofing Ltd's job gallery. Tap a photo to see the roof detail.

Old flat roof decking stripped back to the joists, ready for new boards

Light grey single-ply membrane on a flat roof beside a slate roof slope

Smooth grey coated flat roof with a vent outlet, finished and drying in the sun

Black flat roof covering beside a slate pitched roof, with a stone building behind

New flat roof deck and edge trims before the covering is fitted

Completed felt roof on a rear extension beside brickwork

Felt flat roof between two brick walls with sealed wall junctions

View the full roofing gallery →

Customer testimonials

In our customers' words

A selection of testimonials published on Co Operate Roofing Ltd's website.

Rated 5 stars on GoogleRead our Google reviews →

Absolutely outstanding service from start to finish. Co Operate replaced our entire roof and the finish is immaculate. The team were professional, tidy, and kept us updated throughout. Couldn't recommend them highly enough.

David H.London · June 2026New Roofs

Had a persistent leak that two other roofers couldn't fix. Co Operate found the problem within 20 minutes and sorted it the same day. Honest, fair pricing and brilliant workmanship. Will be using them for all future roofing work.

Sarah M.Sutton · May 2026Roof Repairs

Co Operate installed a full flat roof on our extension. It looks brilliant and the quality of the EPDM membrane is top notch. They even came back a week later to check everything was perfect. Really impressed with the aftercare.

James T.Guildford · April 2026Flat Roofs

Know what happens next

Tell us what needs doing

Call or send your postcode and a description of the roof problem. Photos taken from the ground help explain the job.

Book your free survey

The team inspects the roof and explains the work it needs, including the covering, access and roof details.

Get the price in writing

You receive a written, no-obligation quote with the work set out before you book.

Have the work completed

10-year guarantee on new roofs. A 12-month guarantee on repairs. Fully insured.

Straight answers

Before you book your roof survey

A clear scope, a free written quote and the right details for your roof.

Ask for a free quote

Can you replace a leaking garage roof?

Yes. We survey garage and extension roofs, check the deck and drainage, and quote for the covering and any associated work.

Do you fit roofs around lanterns?

Yes. The rooflight kerb and waterproofing details form part of the roof specification. Our job gallery includes a finished flat roof with a lantern.

Which flat roof material should I choose?

The choice starts with roof size, shape, use and the condition of the deck. We explain EPDM, GRP and felt options at the survey and price the agreed specification.

Is a flat roof meant to be completely level?

It needs a designed fall towards drainage. A level appearance from below does not show the small gradient built into the roof.

Can I put plant pots on my extension roof?

Only a roof designed for that use should carry planting or regular foot traffic. Discuss any intended use before selecting the construction.

Why is the inside ceiling dry beneath standing water?

Ponding and leakage are separate observations. Retained water still deserves investigation even when the covering has not yet allowed water indoors.

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