Flat RoofingContractors

Flat roof systems

GRP fibreglass roofing in Treorchy

Thinking about a GRP roof for a dormer or extension in Treorchy? The finish is rigid and tidy, with trims moulded into the roof rather than glued on. It does need a dry day and a new deck, so we survey first, explain what is involved and give you a fixed written quote with no obligation.

Finished grey GRP fibreglass flat roof with moulded trims on a single-storey extensionComputer-generated example image

Treorchy at a glance

Postcode districts
CF42
Population
about 8,105 (GeoNames)
Council area
Rhondda Cynon Taf County Borough Council
Building approval
Rhondda Cynon Taf County Borough Council building control, or a registered building control approver
Nearest main town
Rhondda, about 2 miles
Guide price region
Wales (−8% on West Midlands rates)

Why choose GRP fibreglass roofing in Treorchy?

GRP is a good fit in Treorchy for roofs with awkward shapes, short runs of upstand and lots of corners, because every detail is laminated in place rather than cut and glued. Where a sheet membrane would need many joins, fibreglass forms one continuous skin across the whole roof.

Treorchy's flat roofs are mostly on lock-up garage blocks on estates, with plenty on bungalows with flat-roofed side extensions and dormers too. Wales averages roughly 1,460 mm of rain a year, among the wettest in Britain, so we design for steady run-off: proper falls, clear outlets and upstands well above the finished roof.

How much does a GRP fibreglass roof cost in Treorchy?

For Treorchy we use Wales rates: £2,750–£4,950 is the guide for a 20 m² extension roof in GRP with a new deck and insulation, VAT included. The fixed price comes after a free survey for new and replacement roofs.

JobGuide price inc VAT
Extension (20 m²), GRP, new deck + insulation£2,750–£4,950
Dormer (8 m²), GRP, scaffold£1,300–£2,450
Single garage (18 m²), GRP fibreglass£1,650–£3,000
Single garage (18 m²), EPDM rubber£1,450–£2,600
Extension (20 m²), EPDM, new deck + insulation£2,600–£4,500

Will a new GRP roof need extra insulation to meet building regulations?

If the roof is over a heated room and you are replacing more than half of it, usually yes. In England, Wales and Northern Ireland that counts as renovating a thermal element, and in Scotland the council's building standards service will say whether a building warrant applies.

GRP pairs well with a warm roof because the new deck boards it needs can sit on top of the insulation. The result is thicker, so we check at survey that there is room under door cills and wall flashings, and that the upstands can finish around 150 mm above the new surface. Where approval is needed we arrange it with building control or building standards.

Unheated, detached garages normally sit outside the thermal rules. See the building regulations page for each nation, or the warm vs cold roof guide for why we avoid cold roofs where we can.

What's included?

  • Moulded GRP trims, kerbs and upstands
  • Coloured UV-stable topcoat, with anti-slip finish on request
  • Resin and glass-mat laminate with taped and reinforced joints
  • New OSB3 or plywood deck, fixed at close centres

Building regulations in Wales

The Welsh Approved Document L applies. Renovating more than half of a roof over a heated room means upgrading it to around 0.16 W/m²K where feasible, and new extension roofs are built to 0.13 W/m²K. Welsh Government guidance is that most re-roofing needs building control approval, so check whenever more than a quarter of a roof is replaced or repaired. We deal with the application as part of the job. More on the rules.

Which nearby areas do we also cover?

GRP fibreglass roofing in Treorchy: questions

Do you cover Treorchy?

Yes. Treorchy is part of our Rhondda Cynon Taf coverage, including postcode districts CF42. Surveys and roofs are carried out by vetted roofing teams working under S&K Property Investments and Improvement Ltd.

Who checks building regulations for a flat roof in Treorchy?

Where the work needs approval it goes to Rhondda Cynon Taf County Borough Council building control, or a registered building control approver. We tell you at the survey whether your job needs it and deal with the paperwork as part of the quote.

How much does a GRP fibreglass roof cost in Treorchy?

£2,750–£4,950 for a 20 m² extension roof in GRP with a new deck and insulation, at Wales guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.

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.

Can GRP be laid over an existing felt roof?

Generally no. GRP needs a clean, dry, rigid timber deck, so the old felt is usually stripped and the boards replaced before laminating.

Other flat roof work in Treorchy

GRP fibreglass roofing in Treorchy: get a fixed price

Free survey and a written fixed quote for replacement and new roofs. No obligation.

Call usGet a guide price