Cowley, Oxfordshire
Two-storey rear extension in Cowley
We plan and build two-storey rear extensions for homeowners in Cowley. A larger kitchen downstairs and an extra bedroom or bathroom upstairs, under one roof. Start with a free site visit, then a written price once the design is agreed.
Cowley and its postcode districts OX1, OX3 and OX4 are part of our Oxfordshire coverage. In Cowley, a two-storey rear extension is worth comparing with the cost of moving once stamp duty, agents' and legal fees are counted.
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 two-storey rear extension cost in Cowley?
A two-storey rear extension in Cowley is priced at £2,020–£3,020 per square metre including VAT as a guide, before kitchen fit-out and fees. South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.
| Size | Guide price inc VAT |
|---|---|
| 3 m × 5 m footprint, two floors (30 m²) | £60,500–£90,500 |
| 4 m × 6 m footprint, two floors (48 m²) | £97,000–£145,000 |
We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.
Do you need planning permission for a two-storey rear extension in Cowley?
The planning route for a two-storey rear extension in Cowley is set by England's householder rules and your council.
England's rules allow a rear extension of more than one storey without an application only when it is no deeper than 3 metres and at least 7 metres from the boundary opposite the rear wall, and never on designated land. Most two-storey schemes need householder planning permission.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.
What are homes in Cowley like to extend?
Commuter semis and detached houses make up much of Cowley, and longer gardens make England's prior approval route for deeper rear extensions worth considering.
How a two-storey rear extension in Cowley comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
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.
Two-storey rear extensions near Cowley
We also build two-storey rear extensions in nearby Oxford (2.5 miles) and Abingdon (5.3 miles).
- Two-storey rear extension in Oxford
- Two-storey rear extension in Abingdon
- Two-storey rear extension in Kidlington
- Two-storey rear extension in Didcot
- Two-storey rear extension in Wallingford
Other work in Cowley:
FAQ
Two-storey rear extension questions in Cowley
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.
Do you handle building control in Cowley?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
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.
How long does a rear extension take to build in Cowley?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
What postcode areas do you cover around Cowley?
Including OX1, OX3 and OX4, and the surrounding Oxfordshire area.
How much does a two-storey rear extension cost in Cowley?
As a guide, £2,020–£3,020 per square metre including VAT for a standard specification. For example, 3 m × 5 m footprint, two floors (30 m²): about £60,500–£90,500 at that rate. Your written price follows the survey.