Mossley Hill · Merseyside

Extensions over a garage in Mossley Hill

We plan and build extensions over a garage for homeowners in Mossley Hill and nearby. Every project starts with a free visit and a design stage priced in writing before any work begins.

What we'd confirm first for a project in Mossley Hill.

Postcode districts
L18
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
Allerton (1 mile), Wavertree (1.5 miles), Childwall (1.5 miles)
Distance to Liverpool
about 3.6 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.

Mossley Hill sits about 3.6 miles from Liverpool. Closer to home, Allerton is 1.0 miles away and Wavertree 1.5 miles.

What it costs in Mossley Hill

Guide prices for extensions over a garage in North West England are around £1,660–£2,420 per m² of new floor space, including VAT. For a typical project with 3 m × 6 m of new first-floor space (18 m²), that's roughly £30,000–£43,500. These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.

SpecPer m²3 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 Mossley Hill

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 Mossley Hill 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.

Garage walls and the door opening

Garage walls are often a single skin of brick or block with piers, and the wide door opening needs a beam over it. Many over-garage extensions need new inner walls or a steel frame to carry the floor and to insulate properly, which we confirm before the design is fixed.

How we'd run your project

  1. Look at the house

    We start in Mossley Hill with a free visit: measurements, photos, a look at the loft and drains, and a frank chat about budget.

  2. Design and approvals

    We draw the extension and check it against the rules for England, then apply for planning permission or a certificate of lawfulness, whichever fits.

  3. Detail and price

    Construction drawings, engineer's calculations and building control sign-off, then a written fixed price for the build.

  4. 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 Mossley Hill

Who handles building regulations for a project in Mossley Hill?

We handle it as part of the project. What's needed in England: building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end. We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.

Which postcodes do you cover around Mossley Hill?

We cover Mossley Hill (L18) and nearby places including Allerton, Wavertree and Childwall, plus the rest of Merseyside. The first site visit is free.

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

Mossley Hill 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.

Do I need to convert the garage as well?

No. You can keep the garage for parking or storage and build only the room above, as long as the floor between them and any door into the house meet fire separation rules. Converting the garage at the same time is often good value, because the walls and foundations may be upgraded anyway.

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

Nearby towns we cover for extensions over a garage:

Other extensions in Mossley Hill

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

Tell us about your house in Mossley Hill and we'll call you back to arrange a free, no-obligation visit.

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