Cowley, Oxfordshire
Side return extension in Cowley
We plan and build side return extensions for homeowners in Cowley. Infilling the narrow passage beside a Victorian or Edwardian back addition. 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. Side returns suit the Victorian and Edwardian terraces found across parts of Oxfordshire, where the kitchen sits in a narrow back addition.
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 side return extension cost in Cowley?
For Cowley we work from the South East England rate: £2,580–£4,260 per square metre of new floor, including VAT, standard specification. South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.
| Size | Guide price inc VAT |
|---|---|
| 2 m wide × 6 m deep (12 m²) | £31,000–£51,000 |
| 2.5 m wide × 7 m deep (17.5 m²) | £45,000–£74,500 |
Ground conditions, glazing, the roof and how far the house is opened up move the final figure within the range.
Do you need planning permission for a side return extension in Cowley?
Whether your side return extension in Cowley needs a planning application depends on its size, your house and any local restrictions.
Side return infills and the side leg of a wraparound are treated as side extensions in England: single-storey, no more than 4 metres high and no wider than half the original house. They are not permitted development in conservation areas, National Parks or National Landscapes, and a joined wraparound often needs a planning application because the side and rear rules apply together.
The Party Wall etc. Act 1996 applies in England: you serve notice two months before work to a shared wall, and one month before digging foundations within 3 metres (or 6 metres for deeper foundations) of a neighbour's building. Neighbours can agree in writing; if they dissent, surveyors agree an award.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. At the first visit we measure what is there now and tell you which route fits: permitted development, prior approval or a planning application.
What are homes in Cowley like to extend?
Around Cowley the housing ranges from inter-war semis to 1960s and 1970s estates with good-sized gardens. Many of the newer estates had permitted development rights removed by condition, so we check the planning history before anything is drawn.
How a side return extension in Cowley comes together
Look round and measure
A free visit to see the back of the house, measure it, check the drains and boundaries and hear what you need.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
Written price, then build
Once the design and approvals are in place, you get a fixed written price and programme, and we build through to sign-off.
Side return extensions near Cowley
Neighbouring places we cover include Oxford (2.5 miles) and Abingdon (5.3 miles).
- Side return extension in Oxford
- Side return extension in Abingdon
- Side return extension in Kidlington
- Side return extension in Didcot
- Side return extension in Wallingford
Other work in Cowley:
FAQ
Side return extension questions in Cowley
Can I get a price without a visit?
Our online guide-price tool gives a range in a couple of minutes. A written price needs a survey.
Is the site visit in Cowley free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
Can I combine a side return with a rear extension?
Yes; that is a wraparound extension, and it gives the biggest open-plan room a terrace can have.
What postcode areas do you cover around Cowley?
Including OX1, OX3 and OX4, and the surrounding Oxfordshire area.
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.