Benfleet over-garage extensions, designed and built
Thinking about an over-garage extension for your Benfleet home? Start with a free site visit: we measure up, check what the council will allow and give you honest guide figures on the day.
- Guide price in BenfleetFrom £25,000 inc VAT
- PlanningHouseholder application needed
- Build time12–18 weeks on site
- Postcode districtsSS7, SS8, SS13
Extensions in and around Benfleet
We cover Benfleet and the postcode districts SS7, SS8, SS13. Neighbouring towns we cover include Hadleigh (2 miles), Canvey Island (2 miles), Rayleigh (3 miles), Wickford (4 miles).
Just over the Kent border, Gravesend is about 11 miles away. 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 much does an over-garage extension cost in Benfleet?
These guide figures apply our East of England adjustment (×1.06) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Benfleet: £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 |
Try the guide-price tool to see a range for your own size and finish.
Planning and approvals in Benfleet
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
When an over-garage extension makes sense
- Families needing a bedroom without losing garden
- Detached and link-detached houses with an attached garage
- Homes where the landing can connect to the new room
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.
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
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.
Your questions about an over-garage extension in Benfleet
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Benfleet, 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 Benfleet?
Yes. We cover Benfleet and the surrounding parts of Essex. Site visits are free and there is no obligation.
How long does an over-garage extension take to build in Benfleet?
On site, typically 12 to 18 weeks once approvals are in place. Before that, allow 8–14 weeks design and approvals.
How much does a room over a garage cost?
Our guide range is about £1,910 to £3,600 per m² including VAT. A single-garage room of about 12 m² usually costs £26,500 to £34,500 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 Benfleet
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.