Dormers · balconies · bays
Fibreglass on Dormers and Balconies
GRP is the usual roof where people walk or stand: balconies, roof terraces, bay window tops and dormers. A small GRP roof costs €2,800 to €6,000, with access at height on top.
Small roofs with lots of edges, and roofs that people stand on.
Free, no obligation. One local company prices it, not five.
Small roofs, lots of edges
A dormer or bay top is mostly edges: trims on three sides, an upstand at the wall, cheeks and a gutter. GRP forms all of that in one material, so there are no laps to open. Access is the cost: scaffolding or a tower at first-floor height, for a few square metres of roof.
A roof you walk on
For walkways and balconies, the heavier 600 g/m² mat is used, against 450 g/m² for most roofs, with anti-slip aggregate in the topcoat. EPDM can be punctured under a hard point load, which is why GRP is the usual choice where people stand.
- Ask for the mat weight in writing.
- Ask how the door threshold and the upstand behind it are detailed.
- Furniture feet on pads, not straight on the topcoat.
What it costs
For a 12 m² dormer or balcony, the typical rate gives €900 to €1,680; access and trims usually push it higher.
| Job | Typical cost | What moves the price |
|---|---|---|
| Dormer, bay top or balcony | €2,800 to €6,000 | Access at first-floor height; the heavier mat on a balcony |
| GRP, a m² | €75 to €140 a m² | On a roof this small, access and trims push it higher |
| Repair: a crack, a trim, an outlet | €250 to €900 | Finding it; a dry day to re-laminate |
GRP jobs we cover
New GRP roofsStrip the old roof and lay GRP. €75 to €140 a m².More on new grp roofs →
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 →
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
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Questions people ask
Is GRP good for a balcony?
It's the usual choice, with the heavier mat and an anti-slip topcoat.
What does a dormer roof in GRP cost?
A small GRP roof is €2,800 to €6,000. Scaffolding or a tower at height adds to it.
Can a balcony over a room be GRP?
Yes, if the build-up under it is right: falls, insulation if the room is heated, and a proper threshold detail. That's one for the roofer to look at.
Get a free price for a GRP roof
One local flat roofing company, a look at the roof, a written price. Free, no obligation.