St Austell, Cornwall
Side return extension in St Austell
Infilling the narrow passage beside a Victorian or Edwardian back addition. If you live in St Austell and want to know what a side return extension would cost and whether it needs planning, start with the online guide price or a free site visit.
We cover St Austell (PL25) as part of our Cornwall work. Side return projects in St Austell usually start with a drainage survey of the side passage.
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 St Austell?
A side return extension in St Austell is priced at £2,390–£3,950 per square metre including VAT as a guide, before kitchen fit-out and fees. South West prices run slightly above our West Midlands baseline; natural stone to match the house is the main variable.
| Size | Guide price inc VAT |
|---|---|
| 2 m wide × 6 m deep (12 m²) | £28,500–£47,500 |
| 2.5 m wide × 7 m deep (17.5 m²) | £42,000–£69,000 |
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 St Austell?
Whether your side return extension in St Austell needs a planning application depends on its size, your house and any local restrictions.
In England the side part of a side return or wraparound must meet the side-extension rules (one storey, under 4 metres high, no more than half the width of the original house), and those rights do not apply on designated land. Because a wraparound combines a side and a rear extension, many need householder planning permission.
Because rear extensions often sit on or near the boundary, the Party Wall etc. Act 1996 usually applies in England. Notices go out one or two months before work depending on the type of work, and a surveyor's award is only needed if a neighbour does not consent.
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 St Austell like to extend?
Stone-built and rendered houses are common around St Austell, so matching the walling is a design decision in its own right: natural stone, reconstituted stone or a render finish across old and new.
How a side return extension in St Austell comes together
Free site visit
We measure the house and garden, look at the back wall, drainage and boundaries, and talk through what you want from the space.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Paperwork handled
Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.
Side return extensions near St Austell
We also build side return extensions in nearby Bodmin (9.2 miles) and Truro (13.5 miles).
- Side return extension in Bodmin
- Side return extension in Truro
- Side return extension in Newquay
- Side return extension in Falmouth
- Side return extension in Redruth
Other work in St Austell:
FAQ
Side return extension questions in St Austell
Do I need a party wall agreement?
In England, usually yes if the extension is on or near a shared boundary or the foundations are close to a neighbour's building. We serve the notices.
What postcode areas do you cover around St Austell?
Including PL25, and the surrounding Cornwall area.
Where does the drainage go?
Side passages often carry the soil and rainwater pipes. We survey them first and reroute them under the new floor where needed.
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.
How long does a rear extension take to build in St Austell?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
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.