North Yorkshire
Rear extensions for semi-detached houses in North Yorkshire
Single or two-storey extensions for semi-detached houses, with side access and one party wall. We design and build rear extensions across North Yorkshire, from York and Middlesbrough to Harrogate, covering single-storey kitchen extensions, two-storey additions, side returns and wraparounds.

In York we measure the attached neighbour's extension at the survey, because it often sets the sensible depth for yours. North Yorkshire has through terraces and some back-to-backs as well as later semis; back-to-backs have little or no rear space, so we look at side or loft options there.
How much does a semi-detached rear extension cost in North Yorkshire?
Guide prices for a semi-detached rear extension in North Yorkshire start from our Yorkshire and the Humber rate of £1,770–£2,880 per square metre, including VAT. Yorkshire prices sit below our West Midlands baseline; matching natural stone is the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £21,000–£34,500 |
| 4 m wide × 5 m deep (20 m²) | £35,500–£57,500 |
| 4 m wide × 6 m deep (24 m²) | £42,500–£69,000 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission in North Yorkshire?
In England a single-storey rear extension can often be built under permitted development: up to 3 metres beyond the original rear wall of an attached house, or 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres if any part is within 2 metres of a boundary.
England's rules allow a rear extension of more than one storey without an application only when it is no deeper than 3 metres and at least 7 metres from the boundary opposite the rear wall, and never on designated land. Most two-storey schemes need householder planning permission.
If 3 or 4 metres is not enough, England's prior approval route allows 6 metres on a terraced or semi-detached house and 8 metres on a detached house for a single-storey rear extension. Neighbours are consulted, the council decides within 42 days, and the fee is £249, rising to £310 from 8 December 2026.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent.
Where in North Yorkshire do we work?
FAQ
Questions people ask
How far can I extend a semi without planning?
3 metres under permitted development in England, or up to 6 metres with prior approval, outside designated land.
Can I match pebbledash or render?
Yes. Many semis are refinished with new render across the whole back elevation so old and new match.
Single or two-storey on a semi?
Two-storey if you need bedrooms, single-storey if you need a bigger kitchen. Planning risk is lower for single-storey.
Do you cover all of North Yorkshire?
We cover 18 towns and districts in North Yorkshire, including York, Middlesbrough and Harrogate.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.