Ely Roofers installs and repairs flat roofs on extensions, garages and outbuildings for homeowners in Cottenham and the villages nearby.
A flat roof is never truly flat. It sits at a very slight fall, typically 1:40 or 1:60, so rainwater drains to an outlet rather than pooling. When that fall is insufficient, or when the membrane fails at a seam or upstand, water backs up and finds its way in.
The main systems used today are EPDM rubber and mineral felt. EPDM is a single-ply rubber membrane that comes in large sheets, reducing the number of seams. Felt is a layered built-up system, usually three layers hot-bonded together. Both are suited to extensions and garages; the right choice depends on the size and shape of the roof, the existing structure, and what is already there.
Choosing the right contractor matters more than most homeowners realise. A flat roof done poorly will fail within a few years, and the repair bill can exceed the original job cost. The questions below are worth asking any contractor before you agree to anything.
Demand for payment in full before work starts is a significant red flag. A reasonable contractor will ask for a deposit, often around 25-30%, with the balance on completion. Pressure to decide on the spot, vague quotes that list only a final price with no breakdown, and an unwillingness to put anything in writing are all signs to walk away.
Be cautious of prices that seem very low. Flat roofing materials have a known cost. A quote that is dramatically cheaper than others usually means thinner felt, fewer layers, no proper stripping back, or corners cut on flashings. A typical small garage roof of around 15-20 square metres, stripped and re-felted or re-covered in EPDM, generally costs somewhere between £800 and £1,800 depending on the system and the condition of the existing deck. Extension roofs of 20-40 square metres can range from £1,500 upwards for a quality system. These are general UK ranges and every job differs, but they give you a baseline for spotting outliers.
Three quotes is the standard advice, and it is good advice, but only if you are comparing like for like. Ask each contractor to quote for the same scope: strip existing covering, inspect and replace any rotten deck boards, supply and fit a named system to the full area including upstands and flashings. If one contractor quotes for overlay and another quotes for a full strip, you cannot meaningfully compare the prices.
When comparing quotes, look at the material specified. Not all felt is the same; a three-layer SBS-modified felt system is a different product from basic torch-on felt. EPDM varies in thickness. Ask what thickness and specification is being used.
Once work starts, you should see the old covering stripped fully before anything new goes on. The timber deck should be checked for soft spots; any rotten boards must be replaced before the new membrane is laid. Falls should be checked with a spirit level or by pouring a small amount of water to confirm it drains correctly.
Flashings where the roof meets the wall should be dressed neatly into the brickwork, either by cutting a chase in the mortar joint or by using a compatible flashing tape, depending on the system. The outlet or outlet pipe should be cleaned and, where necessary, a new flat roof outlet fitted. When the job is finished, the roof surface should be clean, the upstands neat, and there should be no standing water when it rains.
We cover Cottenham and the surrounding villages, as well as jobs in and around Ely itself. If you are unsure whether we cover your area, call us and we will confirm.
To get a proper price for your flat roof in Cottenham, call us for a roof survey. We will look at the existing covering, the deck, the falls and the flashings before we give you a figure, not before.
No obligation · We usually respond within 2 hours
Storm damage, active leak, damaged ridge - we aim to be on-site within 24 hours.
