07447 188036info@gnbroofing.co.uk Serving East AngliaMon–Sat 7am–6pm HomeAboutServicesFlat Roof InstallationFlat Roof ReplacementFlat Roof RepairsEPDM Rubber RoofingSingle-Ply Membrane (SFlex · Sika Plan · Resitrix)Commercial Flat RoofingFascias & Soffits (UPVC)Guttering & BargeboardsCladding — UPVC, Timber-Effect & Composite AreasNorfolk NorwichThorpe St Andrew & SprowstonHellesdonCostesseyTaverhamDraytonCringlefordWymondhamDerehamGreat YarmouthThetfordKing's Lynn County overview Norfolk (county overview)Suffolk (county overview)Cambridgeshire (county overview) Our WorkReviewsContact07447 188036Get Free Quote - Home - Services - Flat Roof Replacement Flat Roof Replacement # Flat Roof ReplacementAcross Norwich &East Anglia Strip the failed covering, put the deck and falls right, upgrade the insulation, and re-cover in a manufacturer-warranted system — for a fixed price with a 20-year product guarantee and a 10-year workmanship guarantee. Get my free fixed-price quote 07447 188036 Free survey · No call-out fees · Written quote in 3–4 days · You deal with Neil directly Flat-roofing specialist Sika Plan Approved Installer 20-yr product / 10-yr workmanship PL & EL fully insured Free fixed-price quotes Service overview ## What we do, who it's for, and when to book it. ### What it is Complete replacement of an existing flat roof — old covering stripped, deck inspected and repaired, insulation upgraded, and a new single-ply or EPDM system installed to current standards. ### Who it's for Owners of properties with old bitumen felt, ageing GRP, tired asphalt or failed single-ply roofs that are leaking, blistering, or past their design life. ### When it's needed When patch repairs are becoming a habit, when the insulation is inadequate, when the deck is soft underfoot, or when a survey shows the covering is beyond economic repair. ### Why it matters Replacing rather than repeatedly patching is almost always cheaper across a 5–10 year window. A proper re-cover resets the guarantee clock, fixes the falls and insulation, and stops the water damage feeding into ceilings, walls and joists. The cost of leaving it ## What actually happens when this is put off. ### If it's ignored - Each winter of freeze-thaw widens micro-cracks and delamination, turning a repairable roof into a full re-deck at 2–3× the cost. - Persistent leaks rot roof joists and wall plates — timber repairs are far more expensive than the roof itself. - Damp travels sideways into cavity walls and insulation, so the visible ceiling stain is usually the smallest part of the problem. ### Common mistakes we clean up after - 'Just overlay it' quotes that trap moisture between the old and new coverings — a two-year fix, not a twenty-year one. - Skipping the insulation upgrade during replacement, then failing Building Control or spending double later. - Choosing a membrane the installer isn't approved for — voids the manufacturer warranty and leaves you with only their word. Our process ## A predictable path from first call to guaranteed sign-off. - 01 Free survey & moisture check We probe the deck, check the falls, and identify what's actually failing so the replacement solves the root cause. - 02 Fixed written quote in 3–4 days A written spec: membrane system, insulation thickness, deck repairs allowed for, upstand and drainage detail. - 03 Strip out & dispose Old covering, insulation and any wet deck lifted and skipped. Included in the price. - 04 Deck repair & falls correction Rotten boards swapped, falls adjusted where needed to eliminate ponding. - 05 Warm-roof build-up Vapour control layer, PIR insulation to current U-value, then the new membrane installed to manufacturer spec. - 06 Detail, clean, guarantee Upstands, outlets and flashings finished, site cleaned, photographs taken, guarantee issued. What you actually get ## The outcomes — not the sales talk. 25–30+ year design life A properly re-covered flat roof outlives the average boiler twice over. 20-year product / 10-year workmanship Written, transferable, and from a Sika Plan Approved Installer. Warmer, cheaper to heat Modern PIR insulation slashes heat loss through the roof — usually the biggest single U-value gain on the property. Fixed price includes disposal Strip, skip and tip fees are all in the quoted number. One crew, start to finish Neil is on site — no subcontracted turnover between strip day and sign-off day. No more patch bills One clean replacement instead of a repair every 18 months. Specification detail ## The technical honest version. Replacement isn't just re-covering. The decision hinges on the state of the deck, whether the insulation meets current regs, and which system best suits the roof's geometry and exposure. ### When re-cover is right vs full replacement If the deck is sound and the falls are correct, an over-lay-clean single-ply install can be right. If there's any deck saturation, soft spots, or historic condensation, full strip-out is the honest answer. ### EPDM for small–medium replacements Garages, porches, small extensions — one-piece EPDM is fast, seamless and cost-effective. ### Single-ply for larger and commercial SFlex or Sika Plan on larger domestic and commercial roofs — mechanically fixed or adhered depending on deck and exposure. ### Resitrix for complex detailing Lots of upstands, pipe penetrations or rooflights? Resitrix self-adhesive EPDM handles it cleanly. ### Insulation upgrade to current regs Any replacement is the moment to upgrade to a warm-roof PIR build-up. It's cheaper to do now than to retrofit later. ### Our specialism Single-ply and EPDM are where our workmanship and warranties are strongest, so that's what we lead with on every replacement. Frequently asked ## Questions we answer at almost every survey. How do I know if I need replacement rather than repair?+Rule of thumb: if you're patching every 12–18 months, if the deck feels soft, if the covering is blistered or delaminated across large areas, or if the insulation is non-existent — it's replacement territory. A free survey tells you either way. How long does replacement take?+Most domestic replacements take 2–5 working days depending on size and deck condition. You'll be weather-tight each evening. Can I stay in the property during the work?+Yes, in almost every case. Access is external, and noise is limited to the strip-out phase. Do you dispose of the old roof?+Yes — skip, tip fees and all disposal is included in the fixed price. Will the ceiling below need repairs after?+The re-cover stops the water source. Any existing stained plasterboard is a separate cosmetic job, which we can advise on but is not included by default. How long is the guarantee?+20 years on the membrane product from the manufacturer, plus 10 years on our workmanship in writing. Do you cover the whole of Norfolk, Suffolk & Cambridgeshire?+Yes. We're based in Norwich (NR5) and work across Norfolk, Suffolk and Cambridgeshire — including all the Norwich suburbs (Thorpe St Andrew, Sprowston, Hellesdon, Costessey, Taverham, Drayton, Cringleford), Wymondham, Dereham, Thetford, Great Yarmouth and King's Lynn. If you're on the edge of that area, phone and ask — we don't charge to travel to quote. Do you charge call-out fees?+No. Surveys and quotes are free, and there are no call-out fees. You get a fixed written price before any work starts — no day-rates, no hidden extras. Who will I actually deal with?+Neil, the owner, personally quotes and runs every job. You won't be handed to a call centre or a subcontracted crew. One point of contact from first call to final sign-off. Where we cover ## Flat Roof Replacement across Norfolk, Suffolk & Cambridgeshire. NorwichThorpe St Andrew & SprowstonHellesdonCostesseyTaverhamDraytonCringlefordWymondhamDerehamGreat YarmouthThetfordKing's LynnNorfolk (county overview)Suffolk (county overview)Cambridgeshire (county overview) Related services ## Also worth looking at. Flat Roof Installation A properly specified, single-ply or EPDM flat roof — installed by a Sika Plan Approved Installer, guaranteed 20 years on materials and 10 years on workmanship, for a fixed written price with zero call-out fees. View service Flat Roof Repairs Track down the actual leak, fix it properly, and tell you honestly whether repair or replacement is the right call — with no call-out fee and a fixed written quote in 3–4 days. View service Single-Ply Membrane (SFlex · Sika Plan · Resitrix) Premium single-ply membrane systems — SFlex, Sika Plan and Resitrix — installed by a Sika Plan Approved contractor with the extended manufacturer warranty that comes with it. View service One next step ## Get a fixed written quote for your flat roof replacement — in 3–4 days. Free survey. No call-out fees. Sika Plan Approved. 20-year product / 10-year workmanship guarantee. Neil quotes it and Neil installs it. Book my free survey Call 07447 188036 Mon–Sat 7am–6pm Flat-roofing specialists serving homes and businesses across East Anglia. Sika Plan Approved. Fully insured. Owner-run by Neil Cockman. Sika Plan Approved Installer ### Services - Flat Roof Installation - Flat Roof Replacement - Flat Roof Repairs - EPDM Rubber Roofing - Single-Ply Membrane - Commercial Flat Roofing - Fascias & Soffits ### Service Areas - Norwich - Thorpe St Andrew & Sprowston - Hellesdon - Costessey - Taverham - Drayton - Cringleford - Wymondham - Dereham - Great Yarmouth - Thetford - King's Lynn - Norfolk (county overview) - Suffolk (county overview) - Cambridgeshire (county overview) ### Contact - 07447 188036 - info@gnbroofing.co.uk - 6 Gilbard RoadNorwich, NR5 8TR - Mon–Sat 7am–6pm · Closed Sun © 2026 GNB Roofing Services. All rights reserved.Privacy PolicyCookie PolicyTerms & Conditions Call NowGet Free Quote We use essential cookies to make this site work, and optional ones only if you accept. Cookie policy. AcceptReject