Belfast, County Antrim
Two-storey rear extension in Belfast
Two-storey rear extension in Belfast: a larger kitchen downstairs and an extra bedroom or bathroom upstairs, under one roof. We measure the house, show you what the rules allow, price it in writing and build it.
Belfast is covered from our County Antrim round, including BT3, BT5, BT7 and BT9. In Belfast, a two-storey rear extension is worth comparing with the cost of moving once stamp duty, agents' and legal fees are counted.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a two-storey rear extension cost in Belfast?
Guide prices for a two-storey rear extension in Belfast start from our Northern Ireland rate of £1,570–£2,350 per square metre, including VAT. Northern Ireland prices are the lowest in our range.
| Size | Guide price inc VAT |
|---|---|
| 3 m × 5 m footprint, two floors (30 m²) | £47,000–£70,500 |
| 4 m × 6 m footprint, two floors (48 m²) | £75,000–£113,000 |
Ground conditions, glazing, the roof and how far the house is opened up move the final figure within the range.
Do you need planning permission for a two-storey rear extension in Belfast?
Whether your two-storey rear extension in Belfast needs a planning application depends on its size, your house and any local restrictions.
Northern Ireland's 2015 Order allows a two-storey rear extension of up to 3 metres where at least 7 metres is left to the rear boundary. Anything larger, or in a conservation area, needs a planning application to the council.
Conservation areas, Areas of Outstanding Natural Beauty and listed buildings restrict permitted development in Northern Ireland. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.
What are homes in Belfast like to extend?
Semis and detached houses are typical of Belfast, and many have room for a rear extension within Northern Ireland's permitted development limits.
How a two-storey rear extension in Belfast comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for council building control.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.
Two-storey rear extensions near Belfast
Close by, we work in Castlereagh, about 2.3 miles away, and Newtownabbey, about 4.4 miles away.
- Two-storey rear extension in Castlereagh
- Two-storey rear extension in Newtownabbey
- Two-storey rear extension in Holywood
- Two-storey rear extension in Dundonald
- Two-storey rear extension in Lisburn
Other work in Belfast:
FAQ
Two-storey rear extension questions in Belfast
What postcode areas do you cover around Belfast?
Including BT3, BT5, BT7, BT9, BT11 and BT13, and the surrounding County Antrim area.
Who will build my extension?
Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.
What is the 45-degree rule?
Many councils check that a two-storey extension does not cross a 45-degree line drawn from the nearest habitable window of the neighbouring house. We test it at the first drawing.
How long does a rear extension take to build in Belfast?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
Do I need a party wall agreement?
Northern Ireland has no Party Wall Act; we agree any shared-wall work with your neighbour in writing.
Is the site visit in Belfast free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.