Extensions over a garage for homes in Heston
A over-garage extension in Heston starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in HestonFrom £31,000 inc VAT
- PlanningHouseholder application needed
- Build time12–18 weeks on site
- Postcode districtsTW3, TW4, TW5, TW7, UB1
Planning and approvals in Heston
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.
Homes in conservation areas, national parks, National Landscapes (formerly AONBs), the Broads and World Heritage Sites have tighter rules, so we always check the property's status and planning history before design starts.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
Covering Heston
We cover Heston and the postcode districts TW3, TW4, TW5, TW7, UB1, UB2. Neighbouring towns we cover include Hounslow (1 mile), Isleworth (2 miles), Southall (2 miles), Hayes (Hillingdon) (3 miles).
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.
What we take care of
- Structural survey of garage walls and foundations
- Strengthening or rebuilding the garage walls if needed
- New floor structure, walls and roof
- Design and householder planning application
- Opening into the existing first floor
- Insulation, electrics, heating and finish
Over-garage extension prices in Heston
These guide figures apply our London adjustment (×1.3) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Heston: £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
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Common questions in Heston
Do you cover all of Heston?
Yes. We cover Heston and the surrounding parts of Greater London. Site visits are free and there is no obligation.
Do I need building regulations approval in Heston?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Heston, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
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.
Does building over a garage need planning permission?
In England and the rest of the UK, adding a storey over a side garage almost always needs a planning application, because two-storey side extensions are outside permitted development.
Book a free site visit in Heston
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.