Darwen, Lancashire
Bungalow rear extension in Darwen
Single-storey rear extensions that keep everything on one level. We design, get the approvals for and build rear extensions for bungalows in Darwen and the surrounding area, with one contract from the first survey to building control sign-off.
We cover Darwen (BB1, BB2 and BB3) as part of our Lancashire work. For Darwen bungalows we design the roof first, because the low eaves decide the height of the new room.
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 bungalow rear extension cost in Darwen?
A bungalow rear extension in Darwen is priced at £1,740–£2,820 per square metre including VAT as a guide, before kitchen fit-out and fees. 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) | £21,000–£34,000 |
| 4 m wide × 6 m deep (24 m²) | £41,500–£67,500 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission for a bungalow rear extension in Darwen?
Planning for a bungalow rear extension in Darwen follows the English householder rules.
In England a single-storey rear extension can often be built under permitted development: up to 3 metres beyond the original rear wall of an attached house, or 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres if any part is within 2 metres of a boundary.
If 3 or 4 metres is not enough, England's prior approval route allows 6 metres on a terraced or semi-detached house and 8 metres on a detached house for a single-storey rear extension. Neighbours are consulted, the council decides within 42 days, and the fee is £249, rising to £310 from 8 December 2026.
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 Darwen like to extend?
Stone and brick terraces are common around Darwen. Where houses back onto a ginnel or alley, deliveries can come in from the rear, which makes the build tidier.
How a bungalow rear extension in Darwen comes together
Look round and measure
A free visit to see the back of the house, measure it, check the drains and boundaries and hear what you need.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
Fixed price and build
A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.
Bungalow rear extensions near Darwen
From Darwen, the nearest places we also cover are Blackburn (3.7 miles) and Haslingden (5.8 miles).
- Bungalow rear extension in Blackburn
- Bungalow rear extension in Haslingden
- Bungalow rear extension in Accrington
- Bungalow rear extension in Great Harwood
- Bungalow rear extension in Ramsbottom
Other work in Darwen:
FAQ
Bungalow rear extension questions in Darwen
What postcode areas do you cover around Darwen?
Including BB1, BB2 and BB3, and the surrounding Lancashire area.
How much does a bungalow rear extension cost in Darwen?
As a guide, £1,740–£2,820 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £21,000–£34,000 at that rate. Your written price follows the survey.
Do I need to move out?
Rarely; the opening into the bungalow is made late in the build.
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.
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.
Do you handle building control in Darwen?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.