County Londonderry
Rear extensions for detached houses in County Londonderry
Wider, deeper rear extensions with room for vaulted roofs and big glazing. Across County Londonderry we handle the whole rear extension: survey, drawings, the planning route, building control and the build. Towns we cover here include Derry~Londonderry, Coleraine and Limavady.
Semis and detached houses are typical of County Londonderry, and many have room for a rear extension within Northern Ireland's permitted development limits.
How much does a detached house rear extension cost in County Londonderry?
In County Londonderry, our guide for a detached house rear extension is £1,700–£2,780 per square metre including VAT for a standard specification. Northern Ireland prices are the lowest in our range.
| Size | Guide price inc VAT |
|---|---|
| 4 m wide × 6 m deep (24 m²) | £40,500–£67,000 |
| 5 m wide × 8 m deep (40 m²) | £68,000–£111,500 |
These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission in County Londonderry?
In Northern Ireland the Planning (General Permitted Development) Order (Northern Ireland) 2015 allows a single-storey rear extension of up to 3 metres on an attached house or 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres within 2 metres of a boundary. Building control approval from the council is still required.
Northern Ireland has no larger-extension prior approval route; anything beyond permitted development needs a planning application.
In Northern Ireland a rear extension of more than one storey can be permitted development if it projects no more than 3 metres and stays at least 7 metres from the rear boundary. Two-storey extensions in conservation areas, and most larger schemes, need planning permission from the council.
Conservation areas, Areas of Outstanding Natural Beauty and listed buildings restrict permitted development in Northern Ireland.
Where in County Londonderry do we work?
FAQ
Questions people ask
Can I have a vaulted ceiling?
Yes, with a pitched roof and exposed or boxed rafters, subject to the height limits.
Is an oak frame worth it?
It is a premium finish with a long life; it costs more than blockwork with a plain roof.
Does a big extension need more heating?
Usually yes. We size underfloor heating or new radiators to the room.
Do you cover all of County Londonderry?
We cover 5 towns and districts in County Londonderry, including Derry~Londonderry, Coleraine and Limavady.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.