Flat RoofingContractors

Flat roof systems

GRP fibreglass roofing across Norfolk

We install GRP fibreglass flat roofs across Norfolk, on homes, rental property and small commercial buildings. Each job starts with a free survey of the joists and deck, and laminating is planned around the weather, because resin needs dry conditions and suitable temperatures to cure properly. You get a fixed written quote first, with no obligation.

Finished grey GRP fibreglass flat roof with moulded trims on a single-storey extensionComputer-generated example image
Price per m²
£79–£147
Typical life
20–40 years
Manufacturer guarantees
20–25 year material warranties on specified systems
Typical garage roof
£1,850–£3,400

Norfolk at a glance

Largest towns
Norwich, Great Yarmouth, King's Lynn, Thetford
Postcode areas
IP, NR, PE
Building control
Norwich City Council, Great Yarmouth Borough Council, Borough Council of King's Lynn and West Norfolk and 1 other council
Neighbouring areas
Suffolk · Cambridgeshire · Essex · Lincolnshire
Guide price region
East of England (+5% on West Midlands rates)

How much does a GRP fibreglass roof cost in Norfolk?

Guide prices including VAT at East of England rates. The fixed price comes after a free survey for new and replacement roofs.

JobGuide price inc VAT
Extension (20 m²), GRP, new deck + insulation£3,150–£5,650
Dormer (8 m²), GRP, scaffold£1,450–£2,800
Single garage (18 m²), GRP fibreglass£1,850–£3,400
Single garage (18 m²), EPDM rubber£1,700–£2,950
Extension (20 m²), EPDM, new deck + insulation£2,950–£5,150

Which flat roofs are common in Norfolk?

Flat roofs in Norfolk sit on 1960s and 1970s link-detached houses with flat-roofed garages and porches, newer estates where the first extension roofs are now being replaced and 1930s semis with flat-roofed garages and kitchen extensions. The East of England is the driest part of Britain, with parts of the Anglian region around 630 mm a year, so summer heat and UV, not rainfall, do most of the ageing on a felt roof. Approximate 1991–2020 regional averages based on Met Office data.

Building regulations in England

Replacing more than half of a roof over a heated room usually counts as renovating a thermal element, so it is insulated to current standards and notified to building control. Renovated roofs over heated rooms are insulated to around 0.16 W/m²K where that's feasible, and new extension roofs are built to 0.15 W/m²K. In Norfolk the application goes to Norwich City Council, Great Yarmouth Borough Council, Borough Council of King's Lynn and West Norfolk and 1 other council. More on the rules.

Why do GRP roofs crack, and can weather affect the installation?

GRP usually cracks where the structure moves and the laminate cannot, typically along board joints, at the junction with trims, or where a roof meets a wall. Weather during laying is the other big factor, because resin cures by chemical reaction and that reaction is sensitive to temperature and moisture.

How we reduce the risk of cracking:

  • boards fixed at close centres so the deck does not flex;
  • joints taped and reinforced with an extra strip of mat;
  • wall junctions finished with a separate trim or flashing, not laminated hard into the masonry;
  • roofs over a certain size divided with movement details where the system calls for them.

And how weather is managed:

  • no laminating in rain, on a damp deck, or when dew or frost is likely before the resin sets;
  • catalyst levels adjusted for the temperature, so resin neither stays tacky on a cold day nor kicks too fast in summer heat;
  • the roof sheeted over if a shower threatens a fresh laminate.

That is why a GRP date can move at short notice. A day's delay costs far less than a laminate that never cures properly.

How long does a GRP roof last, and is it guaranteed?

A properly laid GRP roof typically lasts 20 to 40 years. The range is wide because so much depends on the laminate being fully wetted out, the deck staying dry and stable, and the topcoat being renewed if it wears.

When GRP fails early, the cause is usually one of these:

  • resin laid in damp or cold conditions that never fully cured;
  • cracks at board joints or trims where movement was not allowed for;
  • a deck that was wet, soft or poorly fixed before laminating;
  • a thin or patchy topcoat that has weathered through.

On guarantees, manufacturer material guarantees are available on many specified GRP systems, and some need a registered build-up or an approved installer. Where registration is possible, we do it for you. Every re-roof also comes with our written workmanship guarantee, with the length set out in your quote, and you can ask about insurance-backed options. Read more in our guarantees guide.

Which towns in Norfolk do we cover?

GRP fibreglass roofing in Norfolk: questions

Which towns in Norfolk do you cover?

All of Norfolk. The main towns have their own pages below, and if yours isn't listed we still cover it: send your postcode and we'll confirm.

How much does a GRP fibreglass roof cost in Norfolk?

£3,150–£5,650 for a 20 m² extension roof in GRP with a new deck and insulation, at East of England guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.

Which postcode areas do you cover in Norfolk?

All of Norfolk, including the IP, NR, PE postcode areas. Send your full postcode and we'll confirm.

What colours does a GRP roof come in?

Topcoats are typically available in greys, greens, black and some other shades. Lighter colours absorb less heat, and an anti-slip finish can be added where people will walk on the roof.

Is GRP suitable for a dormer roof?

Yes, GRP is commonly used on dormers because the trims can be moulded neatly and the finish looks tidy from the ground. Scaffold is normally needed, which we include in the quote.

Does GRP smell when it is being laid?

Yes, the resin gives off a strong styrene smell while it cures. It usually fades within a day or so, and we advise keeping nearby windows closed while the team works.

Everything about GRP fibreglass roofing → · All flat roofing in Norfolk →

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