Notting Hill · Greater London

Extensions over a garage in Notting Hill

For an extension over a garage in Notting Hill, the first questions are always the same: how big, which approvals, and what it will cost. This page answers all three for Greater London.

The basics for Notting Hill at a glance.

Postcode districts
W11
County / area
Greater London, England
Price region
London
Guide price
£38,000–£55,000 (£2,100–£3,060 per m²)
Approval route
Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
Nearest towns
Shepherds Bush (0.8 miles), Bayswater (0.9 miles), Queen's Park (1.2 miles)
First visit
Free, no obligation

About an extension over a garage

An extension over a garage is a new first-floor room built on top of an existing attached garage, usually a bedroom, en-suite or study. It uses a footprint you already have, so it adds floor space without taking any garden. The garage walls and foundations often need strengthening or replacing to carry the new floor.

We cover postcode district W11 in and around Notting Hill, along with neighbouring Shepherds Bush, Bayswater and Queen's Park.

What it costs in Notting Hill

In London, which includes Notting Hill, we'd expect an extension over a garage to cost around £38,000–£55,000 for 3 m × 6 m of new first-floor space (18 m²), or £2,100–£3,060 per m² including VAT. The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.

SpecPer m²3 m × 6 m of new first-floor space (18 m²)
Essential£1,930–£2,820 per m²£35,000–£50,500
Standard£2,100–£3,060 per m²£38,000–£55,000
Premium£2,520–£3,670 per m²£45,500–£66,000

Planning and building regulations in Notting 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 Notting Hill homes

Matching the house

A room over a garage usually sits beside the front of the house in full view, so roof form, ridge height, windows and brick matter. Setting the front wall and ridge back slightly from the main house usually helps it look as if it belongs.

Checking the garage foundations

Garages are often built on shallow strip footings sized for a single-storey wall and a light roof. A trial hole shows their depth and condition, and the engineer decides whether they can carry two storeys or need underpinning or new foundations inside the garage.

How we'd run your project

  1. Start at your house

    We come to your home in Notting Hill, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.

  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. Engineer it

    Foundations sized for two floors, steels for any openings, and building control approval, all before anyone starts on site.

  4. Build

    Foundations, walls, floor, roof, windows, then first and second fix. We break through into the house as late as we can.

Questions about extensions over a garage in Notting Hill

Who handles building regulations for a project in Notting 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.

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

Notting 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.

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.

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 my garage take a room on top?

Sometimes, but it needs checking. Many garages are built on shallow footings with thin walls, designed only for a single storey. We dig a trial hole and inspect the walls, and the structural engineer decides whether to reuse them, strengthen them, underpin the footings or build new foundations inside the garage.

Nearby

The same service in neighbouring towns:

Other extensions in Notting Hill

All two-storey extension services in Notting Hill · Extensions over a garage across Greater London

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