Extensions over a garage across Grays
Grays homeowners can use us for the whole over-garage extension project: survey, design, planning or permitted development checks, building regulations and the build itself.
- Guide price in GraysFrom £25,000 inc VAT
- PlanningHouseholder application needed
- Build time12–18 weeks on site
- Postcode districtsRM15, RM16, RM17, RM18, RM20
What is included
- Insulation, electrics, heating and finish
- Strengthening or rebuilding the garage walls if needed
- Opening into the existing first floor
- New floor structure, walls and roof
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.
Planning and approvals in Grays
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.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
Over-garage extension prices in Grays
Prices below are for Grays, using the East of England factor of ×1.06. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Grays: £1,910 to £3,600 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Over a single garage 12 m² | £25,000 – £31,500 | £26,500 – £34,500 | £34,000 – £43,500 |
| Over a large single garage 16 m² | £30,500 – £37,500 | £35,500 – £46,000 | £45,500 – £58,000 |
| Over a double garage 24 m² | £45,500 – £56,000 | £53,000 – £69,000 | £68,500 – £86,500 |
For a figure based on your own dimensions, use our guide-price tool.
Covering Grays
Across RM15, RM16, RM17, RM18, RM20, we can visit, measure and advise. Neighbouring towns we cover include South Ockendon (3 miles), Stanford-le-Hope (6 miles), Basildon (9 miles), Brentwood (10 miles).
The East of England mixes market-town terraces, inter-war semis and modern estates. Clay soils are common in parts of the region, which can affect foundation design.
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
We visit your Grays home, measure up, talk through what you want and check the planning position.
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
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
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 Grays 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.
Do you cover all of Grays?
Yes. We cover Grays and the surrounding parts of Essex. Site visits are free and there is no obligation.
Do I need building regulations approval in Grays?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
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.
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 Grays
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.