Lancashire
Two-storey rear extensions in Lancashire
A larger kitchen downstairs and an extra bedroom or bathroom upstairs, under one roof. Across Lancashire we handle the whole rear extension: survey, drawings, the planning route, building control and the build. Towns we cover here include Preston, Burnley and Blackburn.
In Preston, a two-storey rear extension is worth comparing with the cost of moving once stamp duty, agents' and legal fees are counted. Lancashire 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 much does a two-storey rear extension cost in Lancashire?
In Lancashire, our guide for a two-storey rear extension is £1,690–£2,540 per square metre including VAT for a standard specification. North West prices sit below our West Midlands baseline; access on terraced streets is the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m × 5 m footprint, two floors (30 m²) | £51,000–£76,000 |
| 4 m × 6 m footprint, two floors (48 m²) | £81,000–£122,000 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission in Lancashire?
A two-storey rear extension can be permitted development in England only if it projects no more than 3 metres, stays at least 7 metres from the rear boundary, matches the existing roof pitch and has obscure-glazed upper side windows. In practice most double-storey rear extensions go through a householder planning application.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent.
Where in Lancashire do we work?
FAQ
Questions people ask
Does a two-storey rear extension need planning permission?
Almost always. England and Northern Ireland allow 3 metres without an application only if at least 7 metres remains to the rear boundary; Wales and Scotland are similar or stricter.
Is two-storey cheaper per square metre than single-storey?
Usually yes, because the foundations and roof are shared across twice the floor area. The total cost is higher.
Can I add an en-suite upstairs?
Yes. We plan the soil pipe route early so the bathroom sits where drainage works without boxing through the room below.
Do you cover all of Lancashire?
We cover 28 towns and districts in Lancashire, including Preston, Burnley and Blackburn.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.