Extensions over a garage for homes in South Ruislip
If you live in South Ruislip and want more space without moving, an over-garage extension is one of the most practical ways to get it. We handle the drawings, approvals and the build.
- Guide price in South RuislipFrom £31,000 inc VAT
- PlanningHouseholder application needed
- Build time12–18 weeks on site
- Postcode districtsHA4, UB5
Is an over-garage extension right for your house?
- Homes where the landing can connect to the new room
- Families needing a bedroom without losing garden
- Detached and link-detached houses with an attached garage
Do I need planning permission in South Ruislip?
In England any side extension over one storey, including a room built over a side garage, needs a householder planning application. The fee is £548 from 1 April 2026 and councils aim to decide within 8 weeks.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
Applications are decided by the local planning authority (your district, borough or unitary council).
Working in South Ruislip
We cover South Ruislip and the postcode districts HA4, UB5. Nearby, we also take on projects in Ruislip (1 mile), Northolt (2 miles), Hayes (Hillingdon) (3 miles), Pinner (3 miles).
Just over the Hertfordshire border, Bushey is about 6 miles away. Across London, terraced houses with narrow side returns and tight access are the norm, which shapes everything from party wall notices to how materials reach the back garden.
How much does an over-garage extension cost in South Ruislip?
For South Ruislip we adjust our national guide rates by ×1.3, the factor we use for London. Figures include VAT; your written quote after the survey replaces them.
Typical rates in South Ruislip: £2,340 to £4,420 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Over a single garage 12 m² | £31,000 – £38,500 | £32,500 – £42,500 | £42,000 – £53,500 |
| Over a large single garage 16 m² | £37,000 – £46,000 | £43,500 – £56,500 | £56,000 – £71,000 |
| Over a double garage 24 m² | £56,000 – £69,000 | £65,500 – £84,500 | £84,000 – £106,500 |
Try the guide-price tool to see a range for your own size and finish.
From first visit to completion
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
We visit your South Ruislip home, measure up, talk through what you want and check the planning position.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Questions people ask about over-garage extensions
Will my neighbours in South Ruislip be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for South Ruislip, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Do you cover all of South Ruislip?
Yes. We cover South Ruislip and the surrounding parts of Greater London. Site visits are free and there is no obligation.
Can I keep using the garage during the build?
Usually not for parking. The garage roof is removed and the space below is used for access and props for part of the build.
How much does a room over a garage cost?
Our guide range is about £2,340 to £4,420 per m² including VAT. A single-garage room of about 12 m² usually costs £32,500 to £42,500 at standard spec, more if the garage needs rebuilding.
Book a free site visit in South Ruislip
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.