If you have a flat roof on an extension, garage, or outbuilding in Brundall, choosing the right contractor is the single most important decision you will make.
A flat roof is not truly flat - it is laid to a slight fall, usually around 1:40, so water drains away rather than sitting and soaking in. Get that fall wrong and you will have pooling water within months. The covering itself, whether EPDM rubber or a built-up felt system, needs to be properly bonded and dressed into all upstands, outlets, and abutments for the whole thing to work.
At North Walsham Roofers we install EPDM rubber and felt flat roofing systems on extensions, garages, and outbuildings. Getting the right system starts with understanding what is already there and what the structure will support.
EPDM rubber is a single-ply membrane that, when installed correctly, can last well over two decades. It is bonded to the deck in one sheet where possible, which eliminates the seams that cause most flat roof failures. It handles frost and standing water better than older felt systems, and it stays flexible through temperature changes without cracking.
Traditional felt - also called built-up felt or torch-on felt - is still a sound choice for many garage and outbuilding roofs. It is installed in two or three layers bonded together, with a mineral capsheet on top. Properly laid, a quality torch-on felt roof will last fifteen years or more. The weak points are the joints and flashings, which need to be lapped correctly and sealed at every upstand.
Neither system is universally better. The right choice depends on the deck condition, the pitch, what it will be walked on, and your budget. A contractor who pushes one system on every job without inspecting the existing structure first is worth being cautious about.
This is the part most homeowners find harder than the roofing itself. There is no shortage of people willing to quote on a flat roof, but the quality of work varies enormously. Here is what to look for before you agree to anything.
Ask these questions of any contractor who quotes for your flat roof. A good tradesperson will answer all of them without hesitation.
Pressure to sign on the day is a warning sign. A straightforward flat roof replacement on a garage or extension does not require a snap decision, and no legitimate contractor needs your answer before they leave.
Unusually low quotes often mean one of three things: thinner materials, fewer layers, or skipped prep work. Any of those will shorten the life of the roof considerably. The cheapest job rarely works out cheapest over ten years.
Be wary of any contractor who cannot tell you specifically which membrane or felt system they intend to use, or who cannot name the manufacturer. Brand matters because the material specification affects longevity, and a reputable product comes with a datasheet you can look up yourself.
If someone quotes without going onto the roof or thoroughly inspecting the existing structure, treat that quote with scepticism. You cannot price a flat roof accurately from the ground.
A contractor worth hiring will inspect the deck for softness, rot, and deflection. They will check the fall direction and measure whether it is adequate. They will look at how existing upstands are dressed, where water is currently draining, and whether any abutments to walls or parapets need chasing out and repointing. They will also check the condition of any existing insulation.
All of this should inform the quote. If the deck needs replacing, that cost goes in. If the outlet needs clearing or repositioning, that goes in. A flat roof quote that does not mention the deck, the drainage, or the insulation has not been properly thought through.
Flat roof replacement on a typical single-garage or extension in Brundall is broadly in the range of £900 to £2,500 depending on the size, system chosen, and deck condition. EPDM rubber typically costs a little more than felt per square metre installed, but the longer service life and fewer seams make it the preferred choice for many homeowners. Larger or more complex roofs with parapets, multiple outlets, or significant deck replacement will sit at the higher end or above.
Any quote significantly below this range deserves a direct question about what has been left out.
Based in North Walsham, we work across North Norfolk. Call us to arrange a proper survey of your flat roof so we can tell you exactly what it needs.
No obligation · We usually respond within 2 hours
Storm damage, active leak, damaged ridge - we aim to be on-site within 24 hours.
