Lisburn at a glance
- Postcode districts
- BT17, BT26, BT27, BT28
- Population
- about 77,506 (GeoNames)
- Council area
- Lisburn and Castlereagh City Council
- Building approval
- Lisburn and Castlereagh City Council building control
- Nearest main town
- Belfast, about 7 miles
- Guide price region
- Northern Ireland (−12% on West Midlands rates)
Why choose GRP fibreglass roofing in Lisburn?
GRP is a good fit in Lisburn 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.
Around Lisburn, flat roofs are common on 1930s semis with flat-roofed garages and kitchen extensions and on shops with flat-roofed rear stores below flats. Northern Ireland averages roughly 1,150 mm of rain a year, spread over many wet days, so a roof that sheds water quickly to clear outlets lasts far longer than one that holds puddles.
How much does a GRP fibreglass roof cost in Lisburn?
For Lisburn we use Northern Ireland rates: £2,650–£4,750 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 | £2,650–£4,750 |
| Dormer (8 m²), GRP, scaffold | £1,250–£2,350 |
| Single garage (18 m²), GRP fibreglass | £1,550–£2,850 |
| Single garage (18 m²), EPDM rubber | £1,400–£2,450 |
| Extension (20 m²), EPDM, new deck + insulation | £2,450–£4,300 |
Is GRP better than EPDM, felt or a liquid roof?
GRP is the better choice when you want a rigid, walkable finish, a neat look on a visible roof, or crisp moulded details on a complicated shape. It is not automatically better on a plain garage that nobody steps on.
Strengths: hard surface that takes occasional foot traffic; jointless finish with no laps; trims, kerbs and upstands moulded as part of the roof; choice of topcoat colours; small repairs can be laminated in.
Weaknesses: sensitive to weather while laying; rigid, so it can crack where the structure moves; usually needs a new deck; styrene smell during application; skill-dependent, so workmanship matters more than with sheet systems.
For a simple roof, EPDM rubber is often quicker to lay and more forgiving of movement. Torch-on felt is usually cheaper per square metre. A liquid-applied roof can go over a sound existing surface, larger commercial roofs tend to suit single-ply, and older buildings may already have mastic asphalt worth keeping. The EPDM vs GRP vs felt guide compares the three most common choices.
What's included?
- Moulded GRP trims, kerbs and upstands
- Warm-roof insulation and vapour control layer where the room below is heated
- Coloured UV-stable topcoat, with anti-slip finish on request
- Resin and glass-mat laminate with taped and reinforced joints
Building control in Northern Ireland
In Northern Ireland, Technical Booklet F1 sets roof insulation at 0.18 W/m²K when a roof over a heated room is renovated or newly built, where that's feasible. The district council's building control should be contacted before work starts, and we prepare the details it asks for. More on the rules.
Which nearby areas do we also cover?
GRP fibreglass roofing in Lisburn: questions
Do you cover Lisburn?
Yes. Lisburn is part of our County Antrim coverage, including postcode districts BT17, BT26, BT27, BT28. 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 Lisburn?
Where the work needs approval it goes to Lisburn and Castlereagh City Council building control. 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 Lisburn?
£2,650–£4,750 for a 20 m² extension roof in GRP with a new deck and insulation, at Northern Ireland guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Can you walk on a GRP roof?
Yes, a correctly laid GRP roof takes occasional foot traffic, such as cleaning windows or maintaining plant. For a regular walkway or terrace, an anti-slip topcoat and a suitable specification are needed.
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.
