Barrow in Furness, Cumbria
Semi-detached rear extension in Barrow in Furness
Single or two-storey extensions for semi-detached houses, with side access and one party wall. If you live in Barrow in Furness and want to know what a semi-detached rear extension would cost and whether it needs planning, start with the online guide price or a free site visit.
Barrow in Furness sits in Cumbria, with postcode districts including LA13, LA14 and LA15. Semi-detached houses are common across Cumbria, and their side access makes rear extensions quicker to build.
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 Barrow in Furness?
Guide prices for a semi-detached rear extension in Barrow in Furness start from our North West England rate of £1,790–£2,910 per square metre, including VAT. North West prices sit below our West Midlands baseline; access on terraced streets is the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £21,500–£35,000 |
| 4 m wide × 5 m deep (20 m²) | £35,500–£58,500 |
| 4 m wide × 6 m deep (24 m²) | £43,000–£70,000 |
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 semi-detached rear extension in Barrow in Furness?
The planning route for a semi-detached rear extension in Barrow in Furness is set by England's householder rules and your council.
English permitted development (Class A) allows a single-storey rear extension of 3 metres on a terraced or semi-detached house and 4 metres on a detached one, measured from the original house, with a maximum height of 4 metres and eaves of no more than 3 metres within 2 metres of a boundary.
England's rules allow a rear extension of more than one storey without an application only when it is no deeper than 3 metres and at least 7 metres from the boundary opposite the rear wall, and never on designated land. Most two-storey schemes need householder planning permission.
England also has the larger home extension route: a single-storey rear extension of up to 6 metres on an attached house or 8 metres on a detached house, after prior approval from the council. The council notifies your neighbours and has 42 days to decide; the fee is £249 (£310 for applications made from 8 December 2026). The route is not available on designated land such as conservation areas.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. At the first visit we measure what is there now and tell you which route fits: permitted development, prior approval or a planning application.
What are homes in Barrow in Furness like to extend?
Barrow in Furness has long runs of terraced houses with back yards and alleys, plus 1930s semis further out. Yard extensions on terraces are often single-storey and close to both boundaries.
How a semi-detached rear extension in Barrow in Furness comes together
Free site visit
We measure the house and garden, look at the back wall, drainage and boundaries, and talk through what you want from the space.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for 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.
Semi-detached rear extensions near Barrow in Furness
We also build rear extensions for semi-detached houses in nearby Ulverston (7.9 miles) and Heysham (14.3 miles).
- Semi-detached rear extension in Ulverston
- Semi-detached rear extension in Heysham
- Semi-detached rear extension in Morecambe
- Semi-detached rear extension in Fleetwood
- Semi-detached rear extension in Cleveleys
Other work in Barrow in Furness:
FAQ
Semi-detached rear extension questions in Barrow in Furness
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.
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.
What if my neighbour has already extended?
That can make a matching depth easier to justify. We measure theirs at the survey.
Do I need planning permission for a rear extension in Barrow in Furness?
Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.
What postcode areas do you cover around Barrow in Furness?
Including LA13, LA14 and LA15, and the surrounding Cumbria area.
Do you handle building control in Barrow in Furness?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.