Wraparound extensions in Southampton: design, approvals and build
A wraparound extension in Southampton starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in SouthamptonFrom £40,000 inc VAT
- PlanningUsually a householder application
- Build time14–20 weeks on site
- Postcode districtsSO14, SO15, SO16, SO17, SO18

Working in Southampton
We cover Southampton and the postcode districts SO14, SO15, SO16, SO17, SO18, SO19. The same team covers Hythe (3 miles), Totton (4 miles), Eastleigh (5 miles), Fareham (10 miles), all within easy reach.
In the South East, plenty of houses have already been extended once, which makes checking the remaining permitted development allowance an important early step.
Included in a typical project
- Full internal finish or kitchen-ready shell
- Survey, design and 3D layout options
- Roof with glazing along the side return
- Householder planning application
- Foundations, drainage and any manhole relocation
- Structural design for the corner and openings
The corner is where wraparounds succeed or fail. We usually use a single steel goalpost or a corner post hidden in a pier, and set the glazing so the new room reads as one space rather than two boxes.
How much does a wraparound extension cost in Southampton?
Prices below are for Southampton, using the South East England factor of ×1.12. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Southampton: £2,240 to £4,140 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Compact L-shape 18 m² | £40,000 – £48,500 | £46,000 – £58,500 | £58,000 – £75,000 |
| Medium L-shape 25 m² | £56,000 – £67,500 | £64,000 – £81,500 | £81,000 – £104,000 |
| Large L-shape 32 m² | £71,500 – £86,500 | £82,000 – £104,000 | £103,500 – £133,000 |
Try the guide-price tool to see a range for your own size and finish.
Will the council need to approve it?
In England a wraparound extension is assessed as both a side and a rear extension, and the combination usually falls outside permitted development, so most need a householder planning application (£548 from 1 April 2026).
The planning position for a specific Southampton address depends on its history and any designations, which is why we check it at the first visit.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
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).
Our process, step by step
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
We visit your Southampton home, measure up, talk through what you want and check the planning position.
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
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Common questions in Southampton
Who do I contract with for a wraparound extension in Southampton?
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.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Southampton, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Will my neighbours in Southampton 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.
Is a wraparound better than a side return alone?
It adds far more space, but costs more and needs planning permission more often. Our comparison guide sets the two side by side.
Do wraparound extensions need planning permission?
Usually, yes. In England the side element counts as a side extension and the rear element as a rear extension, and the combination normally falls outside permitted development. A householder application costs £548 in England from 1 April 2026.
Book a free site visit in Southampton
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.