Johnstone, Glasgow and the Clyde
Single-storey rear extension in Johnstone
Single-storey rear extension in Johnstone: ground-floor space across the back of the house, usually for a kitchen, dining or family room. We measure the house, show you what the rules allow, price it in writing and build it.
Johnstone sits in Glasgow and the Clyde, with postcode districts including PA5. A depth of 3 to 4 metres keeps many single-storey rear extensions in Johnstone within permitted development, subject to the house's planning history.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a single-storey rear extension cost in Johnstone?
Guide prices for a single-storey rear extension in Johnstone 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 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission for a single-storey rear extension in Johnstone?
Planning for a single-storey rear extension in Johnstone follows the Scottish householder rules.
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.
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. At the first visit we measure what is there now and tell you which route fits: permitted development or a planning application, plus the building warrant.
What are homes in Johnstone like to extend?
Post-war semis and terraces are common around Johnstone, and many have room for a single-storey rear extension within Class 1A limits.
How a single-storey rear extension in Johnstone comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for the building warrant.
Written price, then build
Once the design and approvals are in place, you get a fixed written price and programme, and we build through to sign-off.
Single-storey rear extensions near Johnstone
Neighbouring places we cover include Paisley (3.2 miles) and Barrhead (5.2 miles).
- Single-storey rear extension in Paisley
- Single-storey rear extension in Barrhead
- Single-storey rear extension in Erskine
- Single-storey rear extension in Renfrew
- Single-storey rear extension in Clydebank
Other work in Johnstone:
FAQ
Single-storey rear extension questions in Johnstone
What postcode areas do you cover around Johnstone?
Including PA5, and the surrounding Glasgow and the Clyde area.
How long does a rear extension take to build in Johnstone?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
Is a flat roof or a pitched roof better?
A warm flat roof keeps the extension low under first-floor windows and suits a roof lantern; a pitched or lean-to roof gives a vaulted ceiling. Both last for decades when built properly.
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.
Can you match the brick or stone on my Johnstone house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.