Extensions over a garage in Hayes (Hillingdon)
We design and build over-garage extensions for houses in Hayes (Hillingdon), with a written price once the survey and design are done and one point of contact throughout.
- Guide price in Hayes (Hillingdon)From £31,000 inc VAT
- PlanningHouseholder application needed
- Build time12–18 weeks on site
- Postcode districtsUB1, UB2, UB3, UB4, UB7
Planning and approvals in Hayes (Hillingdon)
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.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
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).
What we take care of
- Strengthening or rebuilding the garage walls if needed
- Design and householder planning application
- New floor structure, walls and roof
- Insulation, electrics, heating and finish
- Opening into the existing first floor
- 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.
Local to Hayes (Hillingdon)
Postcode districts we cover around Hayes (Hillingdon) include UB1, UB2, UB3, UB4, UB7, UB11. The same team covers Southall (2 miles), South Ruislip (3 miles), Heston (3 miles), Greenford (3 miles), all within easy reach.
For homes towards Surrey, Ashford, Surrey is around 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 Hayes (Hillingdon)?
Prices below are for Hayes (Hillingdon), using the London factor of ×1.3. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Hayes (Hillingdon): £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 |
Want a range for your exact size? The guide-price tool takes about a minute.
How the project works
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
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Your questions about an over-garage extension in Hayes (Hillingdon)
Do you cover all of Hayes (Hillingdon)?
Yes. We cover Hayes (Hillingdon) and the surrounding parts of Greater London. Site visits are free and there is no obligation.
Do I need building regulations approval in Hayes (Hillingdon)?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Who do I contract with for an over-garage extension in Hayes (Hillingdon)?
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.
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.
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 Hayes (Hillingdon)
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.