Scottish Borders
Flat-roof rear extensions in the Scottish Borders
Warm flat roofs with lanterns, parapets and long-life membranes. Across the Scottish Borders we handle the whole rear extension: survey, drawings, the planning route, building control and the build. Towns we cover here include Hawick, Galashiels and Peebles.

Flat roofs are the usual choice for rear extensions because they stay below first-floor windows and take a lantern neatly. Post-war semis and terraces are common around the Scottish Borders, and many have room for a single-storey rear extension within Class 1A limits.
How much does a flat-roof rear extension cost in the Scottish Borders?
Guide prices for a flat-roof rear extension in the Scottish Borders start from our Scotland rate of £1,800–£2,940 per square metre, including VAT. 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 the Scottish Borders?
Scottish householder permitted development (Class 1A) covers many single-storey rear extensions, with a 3 metre eaves limit, a 4 metre height limit and, within 1 metre of a boundary, a depth limit of 3 metres for terraced houses or 4 metres for others. Conservation areas are excluded, and you need a building warrant whatever the planning position.
Insulation and glazing follow Section 6 of the Scottish Technical Handbook; the building warrant drawings show how the extension meets it.
Classes 1A and 1B do not apply in conservation areas, and listed buildings need listed building consent.
Where in the Scottish Borders do we work?
FAQ
Questions people ask
How long does a flat roof last?
A well-built single-ply or GRP warm roof typically lasts 25 years or more.
Is a flat roof really flat?
No; it is built to falls so water drains to outlets or gutters.
Can I walk on it?
Not as a balcony without planning permission and a guarding design; it can be accessed for maintenance.
Do you cover all of the Scottish Borders?
We cover 5 towns and districts in the Scottish Borders, including Hawick, Galashiels and Peebles.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.