Cost guide
Fibreglass Roof Cost in Ireland
A GRP fibreglass roof costs €75 to €140 a m² laid. A whole GRP flat roof on a garage or extension is €2,800 to €6,500, and €3,800 to €6,500 on a 30 to 40 m² rear kitchen extension.
What moves the price, what a written quote should list, and what it costs where you live.
Free, no obligation. One local company prices it, not five.
What a GRP roof costs for your size
One tap: roughly how big the roof is. The deck, trims, outlets, insulation and access move the price.
Your roof area × the typical GRP rate
€2,250 to €4,200
30 m² at €75 to €140 a m² for GRP, laid with trims. An estimate, not a quote.
- A GRP roof on a 30 to 40 m² kitchen extension is €3,800 to €6,500 for the whole job.
- A rotten deck adds €30 to €50 a m².
- Roofing work on a house is at 13.5% VAT, not 23%.
By job and size
| Job | Typical cost | What moves the price |
|---|---|---|
| A GRP flat roof, garage or extension | €2,800 to €6,500 | Size, a new deck, trims on every edge, the outlet |
| GRP on a kitchen extension, 30 to 40 m² | €3,800 to €6,500 | The upstand at the house wall, rooflights |
| Warm GRP roof over a heated extension, 35 to 50 m² | €6,000 to €9,500+ | Insulation boards and taller trims |
| Single garage, 15 to 25 m² | €1,800 to €5,200 | GRP sits in the upper half of this range |
| Dormer, bay top or balcony | €2,800 to €6,000 | Access at first-floor height; the heavier mat on a balcony |
| GRP over the old roof | €1,800 to €5,000 | Only over a dry, sound deck |
| Repair: a crack, a trim, an outlet | €250 to €900 | Finding it; a dry day to re-laminate |
| New OSB3 deck where the old one has rotted | €30 to €50 a m² extra | How much of it is soft |
Whole-job prices. Roofing work on a house is at 13.5% VAT. Small roofs cost more a m²: the trims, outlets and the day's set-up cost much the same on 8 m² as on 30 m².
What GRP costs a square metre
| Membrane | Typical rate | Notes |
|---|---|---|
| GRP fibreglass | €75 to €140 a m² | Laid, with trims and topcoat |
| Warm roof system | €130 to €190 a m² | Insulation above the deck |
| EPDM rubber | €70 to €140 a m² | For comparison |
| Torch-on felt | €55 to €90 a m² | For comparison |
Dublin and the rest
A GRP or warm flat roof, by where you are.
| Where | GRP or warm flat roof | Against rural prices |
|---|---|---|
| Dublin | €4,500 to €9,500+ | 15 to 25% above rural prices |
| The commuter belt | €4,200 to €9,000+ | 5 to 15% above rural prices |
| Cork, Galway and Limerick | €4,000 to €8,500+ | 3 to 8% above rural prices |
| The midlands and rural counties | €3,800 to €8,000+ | the national baseline |
What the written price should list
- Strip and replace, or overlay, and the area in m².
- The deck: new OSB3 boards, all of it or only rotten boards, and the rate if more is found.
- The GRP system by name, the mat weight (450 g/m² for most roofs, 600 g/m² for walkways and balconies) and the topcoat colour.
- Edge trims, outlets, upstands at the wall, and any rooflights.
- Insulation, if any: type and thickness.
- Skip, VAT, and the guarantee in writing: who gives it, for how long, and on what.
GRP jobs we cover
GRP over an existing roofOnly over a dry, sound deck. €1,800 to €5,000.More on grp over an existing roof →
Garage roofsThe commonest roof to go over to GRP. €1,800 to €5,200.More on garage roofs →
Extension roofsWith insulation over a heated room. €3,800 to €6,500 for 30 to 40 m².More on extension roofs →
Dormers and balconiesSmall roofs with lots of edges, and roofs you stand on.More on dormers and balconies →
GRP roof repairCracks, trims, outlets. €250 to €900.More on grp roof repair →Fibreglass roofing in every county
- Carlow1.4% flat main roofs
- Cavan0.8% flat main roofs
- Clare1.2% flat main roofs
- Cork2.5% flat main roofs
- Donegal1.0% flat main roofs
- Dublin3.0% flat main roofs
- Galway1.2% flat main roofs
- Kerry1.8% flat main roofs
- Kildare1.0% flat main roofs
- Kilkenny1.4% flat main roofs
- Laois1.2% flat main roofs
- Leitrim1.2% flat main roofs
- Limerick1.6% flat main roofs
- Longford0.9% flat main roofs
- Louth2.3% flat main roofs
- Mayo2.3% flat main roofs
- Meath1.3% flat main roofs
- Monaghan0.9% flat main roofs
- Offaly1.3% flat main roofs
- Roscommon1.2% flat main roofs
- Sligo1.4% flat main roofs
- Tipperary1.6% flat main roofs
- Waterford2.2% flat main roofs
- Westmeath1.5% flat main roofs
- Wexford2.7% flat main roofs
- Wicklow2.7% flat main roofs
Free quote
Get a price in 4 taps
Tap what you need and leave your number. It goes to one flat roofing company that covers your county, and they ring you back to arrange a look and a written price.
Questions people ask
Is GRP dearer than EPDM?
A little: GRP is €75 to €140 a m² laid, EPDM €70 to €140 a m²; a whole GRP roof €2,800 to €6,500 against €2,500 to €5,800 in EPDM.
Why do GRP prices vary so much?
Size, the state of the deck, insulation, access and the number of details: trims, upstands, outlets, rooflights. A small dormer with three walls round it can cost more a m² than an open garage.
Is a cheaper quote missing something?
Often the new deck, the trims, the skip or VAT. Ask for every item in writing, so you compare the same job.
Does GRP roofing carry 23% VAT?
No. Roofing work on a house is at the 13.5% rate.
Get a free price for a GRP roof
One local flat roofing company, a look at the roof, a written price. Free, no obligation.