Double-storey extensions for homes in Prestwich
If you live in Prestwich and want more space without moving, a double-storey extension is one of the most practical ways to get it. We handle the drawings, approvals and the build.
- Guide price in PrestwichFrom £36,000 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsM7, M8, M25, M45
What we take care of
- Breaking through at both levels, stairs and landing changes where needed
- Building regulations drawings and structural design
- Measured survey, design and planning drawings
- Insulation, plastering, electrics and plumbing to finish
- Foundations sized for two floors
- Ground and first floor structure, roof tied into the existing roof
The roof is what makes a two-storey extension look right or wrong. We match the pitch and materials of the main house wherever possible and plan the upstairs layout around the existing landing so the new rooms feel original rather than bolted on.
Planning and approvals in Prestwich
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.
Homes in conservation areas, national parks, National Landscapes (formerly AONBs), the Broads and World Heritage Sites have tighter rules, so we always check the property's status and planning history before design starts.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
Extensions in and around Prestwich
We cover Prestwich and the postcode districts M7, M8, M25, M45. We also work in nearby Whitefield (1 mile), Radcliffe (3 miles), Salford (3 miles), Swinton (4 miles).
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.
What should I budget for a double-storey extension in Prestwich?
Prices below are for Prestwich, using the North West England factor of ×0.95. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Prestwich: £1,470 to £2,850 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m, two floors 24 m² | £36,000 – £43,500 | £41,000 – £54,000 | £52,000 – £68,500 |
| 4 m × 4 m, two floors 32 m² | £47,000 – £56,500 | £54,500 – £71,500 | £69,500 – £91,500 |
| 4 m × 6 m, two floors 48 m² | £70,500 – £84,500 | £82,000 – £107,500 | £104,500 – £137,000 |
For a figure based on your own dimensions, use our guide-price tool.
How the project works
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
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
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Your questions about a double-storey extension in Prestwich
Do you cover all of Prestwich?
Yes. We cover Prestwich and the surrounding parts of Greater Manchester. Site visits are free and there is no obligation.
Will my neighbours in Prestwich be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
Who do I contract with for a double-storey extension in Prestwich?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Does a double-storey extension need planning permission?
Often, yes. In England a two-storey rear extension can be permitted development only if it projects no more than 3 m and sits at least 7 m from the rear boundary, with matching roof pitch and obscure side windows. Side extensions over one storey always need planning permission. We confirm the route at the survey.
Is a two-storey extension cheaper per square metre?
Usually. Our guide range is about £1,470 to £2,850 per m² of new floor area including VAT, compared with £1,660 to £3,230 per m² for single-storey work, because the foundations and roof are shared across two floors.
Book a free site visit in Prestwich
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.