Antrim, County Antrim
Semi-detached rear extension in Antrim
Thinking about a semi-detached rear extension in Antrim? Single or two-storey extensions for semi-detached houses, with side access and one party wall. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.
Antrim is covered from our County Antrim round, including BT41. In Antrim we measure the attached neighbour's extension at the survey, because it often sets the sensible depth for yours.
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 semi-detached rear extension cost in Antrim?
Guide prices for a semi-detached rear extension in Antrim start from our Northern Ireland rate of £1,650–£2,700 per square metre, including VAT. Northern Ireland prices are the lowest in our range.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £20,000–£32,500 |
| 4 m wide × 5 m deep (20 m²) | £33,000–£54,000 |
| 4 m wide × 6 m deep (24 m²) | £39,500–£64,500 |
These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission for a semi-detached rear extension in Antrim?
Whether your semi-detached rear extension in Antrim needs a planning application depends on its size, your house and any local restrictions.
Northern Ireland's permitted development rules allow a single-storey rear extension of 3 metres on terraced and semi-detached houses and 4 metres on detached houses, with a 4 metre height limit. Listed buildings, conservation areas and houses with removed rights need planning permission from the council.
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.
Northern Ireland has no larger-extension prior approval route; anything beyond permitted development needs a planning application.
Conservation areas, Areas of Outstanding Natural Beauty and listed buildings restrict permitted development in Northern Ireland. At the first visit we measure what is there now and tell you which route fits: permitted development or a planning application.
What are homes in Antrim like to extend?
Semis and detached houses are typical of Antrim, and many have room for a rear extension within Northern Ireland's permitted development limits.
How a semi-detached rear extension in Antrim 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.
Written price, then build
Once the design and approvals are in place, you get a fixed written price and programme, and we build through to sign-off.
Semi-detached rear extensions near Antrim
Neighbouring places we cover include Ballymena (10.4 miles) and Newtownabbey (12.7 miles).
- Semi-detached rear extension in Ballymena
- Semi-detached rear extension in Newtownabbey
- Semi-detached rear extension in Belfast
- Semi-detached rear extension in Lisburn
- Semi-detached rear extension in Magherafelt
Other work in Antrim:
FAQ
Semi-detached rear extension questions in Antrim
What postcode areas do you cover around Antrim?
Including BT41, and the surrounding County Antrim area.
Do I need planning permission for a rear extension in Antrim?
Often not for a single-storey rear extension of up to 3 metres (4 metres detached) under Northern Ireland's permitted development rules, outside conservation areas.
What if my neighbour has already extended?
That can make a matching depth easier to justify. We measure theirs at the survey.
How long does a rear extension take to build in Antrim?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
How much does a semi-detached rear extension cost in Antrim?
As a guide, £1,650–£2,700 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £20,000–£32,500 at that rate. Your written price follows the survey.
Can I get a price without a visit?
Our online guide-price tool gives a range in a couple of minutes. A written price needs a survey.