Extensions over a garage across Johnstone
From the first sketch to final sign-off, we plan and build over-garage extensions in Johnstone and the surrounding Renfrewshire and Inverclyde area.
- Guide price in JohnstoneFrom £23,500 inc VAT
- PlanningPermission and a building warrant needed
- Build time12–18 weeks on site
- Postcode districtsPA5, PA10
Local to Johnstone
Our survey diary covers Johnstone, including PA5, PA10. We also work in nearby Paisley (3 miles), Barrhead (5 miles), Erskine (6 miles), Renfrew (6 miles).
For homes towards Dunbartonshire, Clydebank is around 7 miles away. Across Scotland, extensions follow Scottish planning and building standards, including the building warrant process, which we build into the programme from the start.
Do I need planning permission in Johnstone?
In Scotland, householder permitted development rules (Class 1A for single-storey ground-floor extensions and Class 1B for extensions of more than one storey) allow some smaller extensions without a planning application, within limits on depth, height and distance from the boundary. Conservation areas and listed buildings are more restricted. Separately, almost every extension needs a building warrant from the council before work starts.
The planning position for a specific Johnstone address depends on its history and any designations, which is why we check it at the first visit.
Scotland has no Party Wall Act. Where work affects a shared wall or a neighbour's land, we agree access, protection and making good with your neighbour in writing before work starts.
Applications are decided by your council as planning authority.
Guide prices for Johnstone
For Johnstone we adjust our national guide rates by ×0.98, the factor we use for Scotland. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Johnstone: £1,760 to £3,330 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Over a single garage 12 m² | £23,500 – £29,000 | £24,500 – £32,000 | £31,500 – £40,000 |
| Over a large single garage 16 m² | £28,000 – £34,500 | £32,500 – £42,500 | £42,000 – £53,500 |
| Over a double garage 24 m² | £42,000 – £52,000 | £49,000 – £64,000 | £63,500 – £80,000 |
Want a range for your exact size? The guide-price tool takes about a minute.
Included in a typical project
- Opening into the existing first floor
- Strengthening or rebuilding the garage walls if needed
- Insulation, electrics, heating and finish
- Structural survey of garage walls and foundations
Fitting the new room to the existing landing is the planning puzzle inside the house. We design the connection first, then the roof, so the extension does not end up with awkward steps or a corridor through a bedroom.
Our process, step by step
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Over-garage extension questions answered
Will my neighbours in Johnstone be involved?
If a planning application is needed, the council notifies neighbours. Where work is close to a shared boundary, we agree access and protection with them in writing.
Do I need building regulations approval in Johnstone?
Yes. Almost every extension needs it, whatever the planning route. In Scotland that means a building warrant before work starts.
Who do I contract with for an over-garage extension in Johnstone?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
How much does a room over a garage cost?
Our guide range is about £1,760 to £3,330 per m² including VAT. A single-garage room of about 12 m² usually costs £24,500 to £32,000 at standard spec, more if the garage needs rebuilding.
Can my garage take the weight of a room on top?
Some can and some cannot. Many garages have a single-skin wall or shallow foundations. Our structural engineer checks this before we give a fixed price.
Book a free site visit in Johnstone
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.