Ayrshire
Rear extensions for semi-detached houses in Ayrshire
Single or two-storey extensions for semi-detached houses, with side access and one party wall. Across Ayrshire we handle the whole rear extension: survey, drawings, the planning route, building control and the build. Towns we cover here include Kilmarnock, Ayr and Irvine.
Where a Kilmarnock semi already has a small lean-to at the back, we usually replace it rather than extend it. Post-war semis and terraces are common around Ayrshire, and many have room for a single-storey rear extension within Class 1A limits.
How much does a semi-detached rear extension cost in Ayrshire?
For Ayrshire we work from the Scotland rate: £1,800–£2,940 per square metre of new floor, including VAT, standard specification. Prices in Scotland sit a little below our West Midlands baseline; building warrant fees and drawings are budgeted separately.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £21,500–£35,500 |
| 4 m wide × 5 m deep (20 m²) | £36,000–£59,000 |
| 4 m wide × 6 m deep (24 m²) | £43,500–£70,500 |
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 in Ayrshire?
In Scotland a single-storey rear extension can be permitted development under Class 1A: eaves no higher than 3 metres and an overall height of 4 metres, and where any part is within 1 metre of a boundary it can project no more than 3 metres on a terraced house or 4 metres on other houses. The rights do not apply in conservation areas, and a building warrant is still needed before work starts.
In Scotland an extension of more than one storey is only permitted development (Class 1B) if no part is within 10 metres of any boundary and it is no higher than the existing house, so almost every two-storey rear extension needs planning permission and a building warrant.
Scotland has no larger-extension prior approval route; extensions beyond permitted development need a planning application.
Classes 1A and 1B do not apply in conservation areas, and listed buildings need listed building consent.
Where in Ayrshire do we work?
FAQ
Questions people ask
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.
What if my neighbour has already extended?
That can make a matching depth easier to justify. We measure theirs at the survey.
Do you cover all of Ayrshire?
We cover 9 towns and districts in Ayrshire, including Kilmarnock, Ayr and Irvine.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.