Colne house extensions
We design and build house extensions for homes in Colne and the surrounding Lancashire area, with guide prices adjusted for the region.
- Postcode districtsBB8
- Price regionNorth West England (×0.95)
- Planning rulesEngland
- Site visitFree, no obligation
Planning and building control in Colne
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
In England a two-storey rear extension is permitted development only if it projects no more than 3 m from the original rear wall, sits at least 7 m from the rear boundary, matches the roof pitch and uses obscure, non-opening side windows upstairs. Most two-storey extensions therefore go through a householder planning application, which costs £548 from 1 April 2026 and normally takes about 8 weeks.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
Applications are decided by the local planning authority (your district, borough or unitary council).
What works best for Colne houses?
The North West has a high share of Victorian and Edwardian terraces with rear yards and outriggers, plus large areas of inter-war semis in the suburbs.
The types we would usually look at first for a home in Colne are kitchen extensions, side return extensions and single-storey rear extensions, depending on the garden and how the house is laid out.
Areas we cover around Colne
We cover Colne and the postcode districts BB8. The same team covers Nelson (2 miles), Burnley (5 miles), Accrington (11 miles), Rawtenstall (12 miles), Blackburn (15 miles), all within easy reach. Just over the North Yorkshire border, Skipton is about 10 miles away.
Guide prices for Colne
We publish guide prices so you can budget before anyone visits. For Colne they are adjusted by ×0.95, the factor we use across North West England.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Double-storey extensions | 32 m² | £54,500 – £71,500 |
| Side return extensions | 11 m² | £25,000 – £31,500 |
| Wraparound extensions | 25 m² | £54,500 – £69,000 |
| Orangery extensions | 16 m² | £42,500 – £53,500 |
| Single-storey rear extensions | 20 m² | £38,500 – £49,500 |
| Extensions over a garage | 12 m² | £23,500 – £31,000 |
Choose an extension type
- Annexe extensions · from £52,000
- Wraparound extensions · from £34,000
- Single-storey rear extensions · from £19,500
- Glass box extensions · from £28,500
- Building regulations for extensions · from £850
- Porch extensions · from £3,800
- Orangery extensions · from £28,500
- Kitchen extensions · from £25,500
- Bungalow extensions · from £24,500
- Bedroom extensions · from £24,500
- Extension plans and drawings · from £1,100
- Utility and boot room extensions · from £13,000
- Flat roof extensions · from £19,500
- Planning permission for extensions · from £300
- Pitched roof extensions · from £21,000
- Home office extensions · from £15,000
- Side extensions · from £20,500
- Side return extensions · from £17,000
- Timber frame extensions · from £19,500
- Extensions over a garage · from £22,500
- Double-storey extensions · from £36,000
- Conservatory replacement extensions · from £19,000
Free site visit
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
Fixed written price
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Questions about extensions in Colne
How much does an extension cost in Colne?
Using our North West England factor (×0.95), a standard-spec single-storey extension of 20 m² is a guide £38,500 to £49,500 including VAT, and a 32 m² two-storey extension £54,500 to £71,500. Your written price follows the survey.
How long does an extension take in Colne?
Usually 2 to 4 months of design and approvals, then 10 to 16 weeks on site for a single-storey extension or 16 to 24 weeks for two storeys.
Do you cover all of Colne?
Yes, including the surrounding parts of Lancashire. Site visits are free and there is no obligation.
Will my neighbours need to be told?
If you apply for planning or prior approval the council notifies them, and in England party wall notices may be needed for work near a shared boundary.
Book a free site visit in Colne
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.