Hemel Hempstead at a glance
- Postcode districts
- HP1, HP2, HP3
- Population
- about 95,961 (GeoNames)
- Council area
- Dacorum Borough Council
- Building approval
- Dacorum Borough Council building control, or a registered building control approver
- Nearest main town
- Watford, about 7 miles
- Guide price region
- East of England (+5% on West Midlands rates)
Why choose GRP fibreglass roofing in Hemel Hempstead?
For a garage or extension in Hemel Hempstead that doubles as a step-out space for window cleaning, GRP gives a firmer footing than a rubber membrane. With an anti-slip topcoat it handles light, occasional use, though a full terrace needs its own specification and, in many cases, planning permission.
Around Hemel Hempstead, flat roofs are common on lock-up garage blocks on estates and on bungalows with flat-roofed side extensions and dormers. 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.
How much does a GRP fibreglass roof cost in Hemel Hempstead?
For Hemel Hempstead we use East of England rates: £3,150–£5,650 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.
| Job | Guide 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 |
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?
- Coloured UV-stable topcoat, with anti-slip finish on request
- Moulded GRP trims, kerbs and upstands
- Removal of the old covering and disposal of waste
- Resin and glass-mat laminate with taped and reinforced joints
Building regulations in England
Replacing more than half of a flat roof over a heated room usually counts as renovating a thermal element, so the roof is insulated to around 0.16 W/m²K where that's technically and economically feasible, and the work is notified to building control: the council or a registered building control approver, unless a registered competent person self-certifies it. A roof on a new extension is built to 0.15 W/m²K. Patch repairs, and most unheated detached garages, don't trigger the upgrade. Structural changes, or a new covering that adds 15% or more to the roof's weight, also need approval. More on the rules.
Which nearby areas do we also cover?
GRP fibreglass roofing in Hemel Hempstead: questions
Do you cover Hemel Hempstead?
Yes. Hemel Hempstead is part of our Hertfordshire coverage, including postcode districts HP1, HP2, HP3. 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 Hemel Hempstead?
Where the work needs approval it goes to Dacorum 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 Hemel Hempstead?
£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.
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.
Can a cracked GRP roof be repaired?
Often, yes. The area is ground back, cleaned and re-laminated with fresh mat and topcoat. If cracks keep returning along joints, the deck or detailing usually needs attention rather than another patch.