Extensions in Swanage: design, planning and build
Planning an extension in Swanage? Compare extension types, see guide prices adjusted for Swanage and book a free site visit.
- Postcode districtsBH19
- Price regionSouth West England (×1.02)
- Planning rulesEngland
- Site visitFree, no obligation
Covering Swanage and nearby
Site visits are available across Swanage (BH19). Neighbouring towns we cover include Poole (7 miles), Bournemouth (9 miles), Christchurch (12 miles), Ferndown (14 miles), Wimborne Minster (14 miles). Just over the Hampshire border, New Milton is about 17 miles away.
Popular extension prices in Swanage
Every figure below is a guide for Swanage, adjusted for South West England build costs (×1.02) and including VAT. Design and council fees are shown separately on each page.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Wraparound extensions | 25 m² | £58,500 – £74,000 |
| Orangery extensions | 16 m² | £45,500 – £57,500 |
| Extensions over a garage | 12 m² | £25,500 – £33,500 |
| Side return extensions | 11 m² | £26,500 – £34,000 |
| Single-storey rear extensions | 20 m² | £41,500 – £53,500 |
| Double-storey extensions | 32 m² | £58,500 – £77,000 |
Planning rules in Swanage
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
In England a single-storey side extension can be permitted development if it is no more than 4 m high and no wider than half the width of the original house. Two-storey side extensions, and any side extension on designated land such as a conservation area, need a householder planning application.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
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).
Choosing the right extension in Swanage
In the South West, local stone, render and brick vary from town to town, so matching materials is a big part of designing an extension that looks right.
Start by comparing orangery extensions, annexe extensions and pitched roof extensions: between them they cover most of the layouts we see requested for houses like these.
Every extension type in Swanage
- Single-storey rear extensions · from £21,000
- Extension plans and drawings · from £1,200
- Home office extensions · from £16,000
- Annexe extensions · from £56,000
- Pitched roof extensions · from £22,500
- Orangery extensions · from £30,500
- Timber frame extensions · from £21,000
- Extensions over a garage · from £24,000
- Double-storey extensions · from £38,500
- Bedroom extensions · from £26,500
- Planning permission for extensions · from £350
- Conservatory replacement extensions · from £20,000
- Bungalow extensions · from £26,500
- Porch extensions · from £4,050
- Building regulations for extensions · from £900
- Wraparound extensions · from £36,500
- Utility and boot room extensions · from £14,000
- Glass box extensions · from £30,500
- Flat roof extensions · from £21,000
- Side return extensions · from £18,000
- Kitchen extensions · from £27,500
- Side extensions · from £22,000
Free site visit
We visit your Swanage 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
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Questions about extensions in Swanage
How much does an extension cost in Swanage?
Using our South West England factor (×1.02), a standard-spec single-storey extension of 20 m² is a guide £41,500 to £53,500 including VAT, and a 32 m² two-storey extension £58,500 to £77,000. Your written price follows the survey.
How long does an extension take in Swanage?
Usually 2 to 4 months of design and approvals, then 10 to 16 weeks on site for a single-storey extension or 16 to 24 weeks for two storeys.
Do you handle building regulations?
Yes. We prepare the drawings and calculations, submit them and book inspections, ending with a completion certificate.
Do you cover all of Swanage?
Yes, including the surrounding parts of Dorset. Site visits are free and there is no obligation.
Book a free site visit in Swanage
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.