Dorset
Two-storey rear extensions in Dorset
A larger kitchen downstairs and an extra bedroom or bathroom upstairs, under one roof. Rear extensions in Dorset: we cover 14 towns including Bournemouth, Poole and Weymouth, with design, approvals and the build under one contract.
In Bournemouth, a two-storey rear extension is worth comparing with the cost of moving once stamp duty, agents' and legal fees are counted. Dorset has Victorian terraces nearer the centre and post-war semis on the edges. Sloping gardens are frequent, which affects floor levels and steps down to the patio.
How much does a two-storey rear extension cost in Dorset?
In Dorset, our guide for a two-storey rear extension is £1,870–£2,810 per square metre including VAT for a standard specification. 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 |
|---|---|
| 3 m × 5 m footprint, two floors (30 m²) | £56,000–£84,000 |
| 4 m × 6 m footprint, two floors (48 m²) | £90,000–£135,000 |
These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission in Dorset?
A two-storey rear extension can be permitted development in England only if it projects no more than 3 metres, stays at least 7 metres from the rear boundary, matches the existing roof pitch and has obscure-glazed upper side windows. In practice most double-storey rear extensions go through a householder planning application.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent.
Where in Dorset do we work?
FAQ
Questions people ask
Does a two-storey rear extension need planning permission?
Almost always. England and Northern Ireland allow 3 metres without an application only if at least 7 metres remains to the rear boundary; Wales and Scotland are similar or stricter.
Is two-storey cheaper per square metre than single-storey?
Usually yes, because the foundations and roof are shared across twice the floor area. The total cost is higher.
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.
Do you cover all of Dorset?
We cover 14 towns and districts in Dorset, including Bournemouth, Poole and Weymouth.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.