Extensions over a garage in Golborne

Golborne: the key facts for this kind of project.

Postcode districts: WA12
County / area: Merseyside, England
Price region: North West England
Guide price: £30,000–£43,500 (£1,660–£2,420 per m²)
Approval route: Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
Nearest towns: Newton-le-Willows (1.9 miles), Abram (2.2 miles), Ashton-in-Makerfield (2.2 miles)
Distance to Liverpool: about 16.4 miles
First visit: Free, no obligation

About an extension over a garage

An extension over a garage suits you if you have an attached single garage beside the house and need an extra bedroom or a larger main bedroom with an en-suite. You get an inspection of the garage structure, a design that matches the house, the approvals your nation needs, structural design, building regulations approval and the build, carried out by vetted teams working under S&K.

Around Golborne we also work in Newton-le-Willows, Abram and Ashton-in-Makerfield, and across the rest of Merseyside. Postcode district in and near Golborne: WA12.

What it costs in Golborne

Using our North West England rates, an extension over a garage with 3 m × 6 m of new first-floor space (18 m²) comes to about £30,000–£43,500, including VAT. Bigger or more glazed designs cost more per m². Design fees, structural calculations and approval fees are separate and listed on our prices page.

Spec	Per m²	3 m × 6 m of new first-floor space (18 m²)
Essential	£1,530–£2,230 per m²	£27,500–£40,000
Standard	£1,660–£2,420 per m²	£30,000–£43,500
Premium	£1,990–£2,910 per m²	£36,000–£52,500

Planning and building regulations in Golborne

In England, most garages sit beside the house, so building over one makes a two-storey extension beyond a side wall, which always needs planning permission. If the garage is at the rear, the 3 m and 7 m rules for two-storey rear extensions apply, measured from the original house. A householder application costs £548 (or £575 for applications made from 8 December 2026).

Approval in England: Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.

Building regulations: Building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end.

Design points for Golborne homes

Fire separation

If the garage stays a garage, the floor between it and the room above, and any door into the house, must give fire separation under building regulations. That usually means fire-resisting plasterboard ceilings, sealed gaps and a fire door, which we design in from the start.

Floor levels and headroom

Garage floors are often lower than the house, and the new first floor may not line up with the existing landing. We set the floor level to avoid awkward steps upstairs, while keeping enough headroom in the garage below for a car or storage.

How we'd run your project

Free site visit
We visit your home in Golborne, look at the structure, access and boundaries, and talk through what you want the new rooms to do.
Choose the approval route
Some designs fit permitted development, most need a householder application. We decide which applies in England before drawing in detail.
Structure and building control
A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.
Build it
The new structure goes up first, then we open into the house, finish inside and get the completion certificate.

Questions about extensions over a garage in Golborne

How long does an extension over a garage take?

Allow 4 to 8 weeks for survey and design, then the approval period (councils should decide householder applications within 8 weeks of validation), then 4 to 8 weeks of technical design, which can overlap. The build itself usually takes 14 to 20 weeks, longer for large or complex designs.

Do I need planning permission for an extension over a garage in Golborne?

Golborne is in England, so England planning rules apply. Planning permission is needed: in England, permitted development only allows single-storey extensions to the side. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

Which postcodes do you cover around Golborne?

We cover Golborne (WA12) and nearby places including Newton-le-Willows, Abram and Ashton-in-Makerfield, plus the rest of Merseyside. The first site visit is free.

How do I get into a room over the garage?

Usually through a new opening off the existing landing or a bedroom, so the stairs stay where they are. If the floor levels do not match, a step or two may be needed inside the new room. Where a landing opening is not practical, a new stair from a converted garage is an option.

Can I add an en-suite above the garage?

Yes, and it is a common choice for a main bedroom. The en-suite needs an extract fan under Part F, a route for the soil pipe down to the drains and enough fall for the waste, which can be harder over a garage. We plan the pipe route through the garage or an outside wall early.

Nearby

We also cover places near Golborne, including:

Other extensions in Golborne

All two-storey extension services in Golborne · Extensions over a garage across Merseyside

Book a free site visit in Golborne and we'll tell you what's possible, what approvals you need and what the design stage would cost.