- Guide price
- £2,450–£4,300
- Survey
- Free for new and replacement roofs
- Quote
- Fixed, in writing
- Coverage
- England, Wales, Scotland, NI
Belfast at a glance
- Largest towns
- Belfast
- Postcode areas
- BT
- Building control
- Belfast City Council
- Neighbouring areas
- County Down · County Antrim · County Armagh · County Tyrone
- Guide price region
- Northern Ireland (−12% on West Midlands rates)
How much does a flat roof replacement cost in Belfast?
Guide prices including VAT at Northern Ireland rates. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Extension (20 m²), EPDM, new deck + insulation | £2,450–£4,300 |
| Single garage (18 m²), torch-on felt | £1,350–£2,300 |
| Extension (20 m²), GRP, new deck + insulation | £2,650–£4,750 |
| Single garage (18 m²), EPDM rubber | £1,400–£2,450 |
Which flat roofs are common in Belfast?
Flat roofs in Belfast sit on terraced streets with flat-roofed rear kitchens and bathrooms, 1930s semis with flat-roofed garages and kitchen extensions and newer estates where the first extension roofs are now being replaced. 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. Approximate 1991–2020 regional averages based on Met Office data.
Building control in Northern Ireland
In Northern Ireland, renovating or replacing a roof over a heated room usually means meeting Technical Booklet F1, and building control should be contacted before work starts. Technical Booklet F1 sets roof insulation at 0.18 W/m²K when a roof over a heated room is renovated or newly built, where feasible. In Belfast the application goes to Belfast City Council. More on the rules.
How long does it take to replace a flat roof?
A garage or single-storey extension roof is usually stripped and re-covered in one to three working days; larger, higher or more detailed roofs take longer. Weather sets the pace, because the deck must be dry before insulation and membrane go down.
We strip only as much as can be made weathertight that day, so the roof is never left open overnight. Expect noise and some vibration during the strip, a skip on the drive (or on the road with a permit) and ladders or a tower against the house. Rooms below stay usable, though it helps to clear shelves near the ceiling. Resin systems such as GRP smell strongly while they cure, so keep nearby windows closed that day. Two-storey roofs need scaffold, which goes up before we start and comes down after sign-off.
Which towns in Belfast do we cover?
Flat roof replacement in Belfast: questions
Which towns in Belfast do you cover?
All of Belfast. The main towns have their own pages below, and if yours isn't listed we still cover it: send your postcode and we'll confirm.
How much does a flat roof replacement cost in Belfast?
£2,450–£4,300 for a 20 m² extension roof in EPDM 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.
Which postcode areas do you cover in Belfast?
All of Belfast, including the BT postcode areas. Send your full postcode and we'll confirm.
Is VAT charged on a flat roof replacement?
Yes, roof replacement is standard-rated at 20%, and an insulated replacement is treated as a single supply. Our guide prices already include VAT.
Do I need to be at home while the roof is replaced?
Not for most of the job, as long as the team can reach the roof and there is room for a skip. We ask you to be there at the start to agree the plan and at the end to look over the finished roof.
What time of year is best for a flat roof replacement?
Late spring to early autumn gives the most reliable dry spells, but a roof can be replaced in any season when the forecast allows. Adhesives and resins have minimum application temperatures, so winter work is planned around mild, dry days.
Everything about flat roof replacement → · All flat roofing in Belfast →