Extensions over a garage across Southport
Southport 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 SouthportFrom £22,500 inc VAT
- PlanningHouseholder application needed
- Build time12–18 weeks on site
- Postcode districtsPR8, PR9
When an over-garage extension makes sense
- Detached and link-detached houses with an attached garage
- Homes where the landing can connect to the new room
- Families needing a bedroom without losing garden
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.
Do I need planning permission in Southport?
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).
Working in Southport
Site visits are available across Southport (PR8, PR9). Neighbouring towns we cover include Formby (7 miles), Maghull (9 miles), Litherland (12 miles), Kirkby (12 miles).
Across the North West, terraced houses with small rear yards suit compact rear and side return extensions, while suburban semis have room for more.
Guide prices for Southport
Prices below are for Southport, using the North West England factor of ×0.95. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Southport: £1,710 to £3,230 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Over a single garage 12 m² | £22,500 – £28,000 | £23,500 – £31,000 | £30,500 – £39,000 |
| Over a large single garage 16 m² | £27,000 – £33,500 | £31,500 – £41,500 | £41,000 – £52,000 |
| Over a double garage 24 m² | £41,000 – £50,500 | £47,500 – £62,000 | £61,500 – £78,000 |
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
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
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 Southport
Do I need building regulations approval in Southport?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Do you cover all of Southport?
Yes. We cover Southport and the surrounding parts of Merseyside. Site visits are free and there is no obligation.
How long does an over-garage extension take to build in Southport?
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 £1,710 to £3,230 per m² including VAT. A single-garage room of about 12 m² usually costs £23,500 to £31,000 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 Southport
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.