Covering Darwen
Our coverage around Darwen (BB3) also includes Blackburn, Accrington and Chorley.
Homes in the North West
The North West has long rows of Victorian terraced houses in its towns and cities, alongside inter-war semis and post-war estates, so rear extensions, dormer lofts and kitchen extensions are common projects.
What does a double-storey extension involve?
Two-storey work has to sit comfortably with the house and the neighbours, so most of the design effort goes into the roofline, window positions and how the new first floor connects to the landing. We handle the planning application, the structural design and the building control process, then build, roof and finish both floors.
- Measured survey, design and planning drawings
- Structural engineer’s design and calculations
- Windows, insulation, plastering, electrics and plumbing
How much should I budget for a double-storey extension?
What double-storey extensions typically cost. These are guide ranges; the written quote for your house replaces them.
| Double-storey extensions | Guide price incl. VAT |
|---|---|
| Standard specification | £2,400 to £2,900 per m² |
| Good specification | £2,900 to £3,400 per m² |
| High specification | £3,400 to £3,850 per m² |
How is a double-storey extension approved in Darwen?
In England we deal with the council’s planning team for permission or a lawful development certificate, with building control (the council or a registered building control approver) for inspections, and with neighbours under the Party Wall etc. Act 1996 where it applies.
Two-storey rear extensions can sometimes be permitted development in England (no more than 3 m deep, at least 7 m from the rear boundary, roof pitch to match), but most two-storey and all two-storey side extensions need householder planning permission. Expect around eight weeks for a decision once the application is validated.
What can affect a double-storey extension?
- Side extensions close to a boundary are often set back or stepped down so they do not create a terraced effect.
- The first-floor link can mean moving a bathroom or reshaping the landing.
What happens after I enquire?
- Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
- Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
- Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
- We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.
What people ask before starting
How much does a two-storey extension cost?
Typically about £2,400 to £3,850 per square metre of new floor area including VAT. A 40 m² extension across two floors is often around £100,000 to £150,000 depending on specification.
How long does a two-storey extension take?
Around 14 to 24 weeks on site, plus the planning period before that.
Who deals with the council for a project in Darwen?
We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.
Double-storey extensions near Darwen
- Double-storey extensions in Blackburn
- Double-storey extensions in Accrington
- Double-storey extensions in Chorley
- Double-storey extensions in Rawtenstall
Learn more about double-storey extensions, or see every project we cover in Darwen.