- Guide price
- £650–£1,100
- Survey
- Free for new and replacement roofs
- Quote
- Fixed, in writing
- Coverage
- England, Wales, Scotland, NI
County Antrim at a glance
- Largest towns
- Lisburn, Newtownabbey, Carrickfergus, Ballymena
- Postcode areas
- BT
- Building control
- Lisburn and Castlereagh City Council, Antrim and Newtownabbey Borough Council, Mid and East Antrim Borough Council and 1 other council
- Neighbouring areas
- Belfast · County Down · County Armagh · County Londonderry
- Guide price region
- Northern Ireland (−12% on West Midlands rates)
How much does a porch or bay roof cost in County Antrim?
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 |
|---|---|
| Porch or bay (4 m²), EPDM | £650–£1,100 |
| Single garage (18 m²), EPDM rubber | £1,400–£2,450 |
| Extension (20 m²), GRP, new deck + insulation | £2,650–£4,750 |
Which flat roofs are common in County Antrim?
Flat roofs in County Antrim sit on bungalows with flat-roofed side extensions and dormers, shops with flat-roofed rear stores below flats and terraced streets with flat-roofed rear kitchens and bathrooms. 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 County Antrim the application goes to Lisburn and Castlereagh City Council, Antrim and Newtownabbey Borough Council, Mid and East Antrim Borough Council and 1 other council. More on the rules.
Which material looks best on a porch or bay roof?
For most porches, EPDM rubber gives a neat, dark grey finish that sits quietly on the front of a house, and on a small roof it can usually be laid as one piece. For angled bays and curved canopies, GRP fibreglass or a liquid-applied system follows the shape without folds or joins.
Many older bay windows and porches were finished in lead, which has a distinctive look. Where you want to keep that appearance, especially on a period house, we can discuss a lead-look finish or retaining lead flashings at the wall. On a listed building or in a conservation area, changing from lead to a membrane may need consent, so we check that at survey.
Colour matters more here than on a hidden rear roof. GRP topcoats come in several colours, and EPDM is typically black or dark grey.
Do I need permission to re-roof a porch or bay?
Usually not. Re-covering a porch or bay roof without materially changing how it looks does not normally need planning permission, and an unheated open porch is not usually a thermal element.
The picture changes if the bay or porch is part of a heated room: replacing most of the roof can then bring it under the insulation rules for renovated roofs, which may need building control approval in England, a check in Wales, building standards in Scotland or district council building control in Northern Ireland. On a very small roof, adding insulation may not be technically feasible because of the height available below the window sill above. We assess that at survey.
Listed buildings need consent for changes that affect their character, and conservation areas can restrict changes to the front of a house. See our building regulations page for more detail.
Which towns in County Antrim do we cover?
Porch, bay and canopy roofs in County Antrim: questions
Which towns in County Antrim do you cover?
All of County Antrim. 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 porch or bay roof cost in County Antrim?
£650–£1,100 for a small 4 m² porch or bay roof in EPDM, 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 County Antrim?
All of County Antrim, including the BT postcode areas. Send your full postcode and we'll confirm.
How long will a new porch roof last?
With good specification and maintenance, EPDM is indicatively 25–50 years and GRP 20–40.
Can a canopy over a front door be re-covered?
Yes. Small canopies are re-covered in the same way as porches, usually in EPDM or GRP, subject to the minimum charge.
Why is my porch roof leaking when the felt looks fine?
The water is often coming from the wall junction, not the roof surface. A failed flashing, cracked mortar or porous brick above can let water in behind the upstand.
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