Extensions over a garage in Bangor (Gwynedd and Anglesey)

Before you start in Bangor (Gwynedd and Anglesey), here's what applies.

Postcode districts: LL57 and LL58
County / area: Gwynedd and Anglesey, Wales
Price region: Wales
Guide price: £29,000–£42,000 (£1,610–£2,350 per m²)
Approval route: Can be permitted development in Wales if it is 10.5 m from the side boundary, set back 1 m from the front and doesn't widen the house by more than half; otherwise planning permission.
Nearest towns: Menai Bridge (1.7 miles), Bethesda (4.3 miles), Llangefni (7.7 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.

Around Bangor (Gwynedd and Anglesey) we also work in Menai Bridge, Bethesda and Llangefni, and across the rest of Gwynedd and Anglesey. Postcode districts in and near Bangor (Gwynedd and Anglesey): LL57 and LL58.

What it costs in Bangor (Gwynedd and Anglesey)

Most of the cost of an extension over a garage is set by its size and specification. For Bangor (Gwynedd and Anglesey) and the rest of Wales, our guide is £1,610–£2,350 per m² including VAT, so about £29,000–£42,000 for 3 m × 6 m of new first-floor space (18 m²). These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.

Spec	Per m²	3 m × 6 m of new first-floor space (18 m²)
Essential	£1,480–£2,160 per m²	£26,500–£39,000
Standard	£1,610–£2,350 per m²	£29,000–£42,000
Premium	£1,930–£2,820 per m²	£35,000–£50,500

Planning and building regulations in Bangor (Gwynedd and Anglesey)

In Wales, building over a side garage can be permitted development if the result is at least 10.5 m from the boundary opposite the side wall, set back at least 1 m from the front of the house and does not widen the house by more than 50%. Garages close to the boundary usually fail these tests, so a householder application costing £585 is often needed.

Approval in Wales: Householder planning application: £585. Councils normally decide householder applications within 8 weeks.

Building regulations: Building regulations approval under the Welsh Approved Documents, which differ from England's in places (notably energy efficiency).

Design points for Bangor (Gwynedd and Anglesey) homes

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.

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

Understand the brief
At your home in Bangor (Gwynedd and Anglesey) we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.
Choose the approval route
Some designs fit permitted development, most need a householder application. We decide which applies in Wales before drawing in detail.
Technical design
We prepare the building regulations drawings, structural calculations and specification so the build price can be fixed.
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 Bangor (Gwynedd and Anglesey)

Who handles building regulations for a project in Bangor (Gwynedd and Anglesey)?

We handle it as part of the project. What's needed in Wales: building regulations approval under the Welsh Approved Documents, which differ from England's in places (notably energy efficiency). 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 Bangor (Gwynedd and Anglesey)?

We cover Bangor (Gwynedd and Anglesey) (LL57 and LL58) and nearby places including Menai Bridge, Bethesda and Llangefni, plus the rest of Gwynedd and Anglesey. The first site visit is free.

Do I need planning permission for an extension over a garage in Bangor (Gwynedd and Anglesey)?

Bangor (Gwynedd and Anglesey) is in Wales, so Wales planning rules apply. Can be permitted development in Wales if it is 10.5 m from the side boundary, set back 1 m from the front and doesn't widen the house by more than half; otherwise planning permission. 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.

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.

Nearby

We also cover places near Bangor (Gwynedd and Anglesey), including:

Other extensions in Bangor (Gwynedd and Anglesey)

All two-storey extension services in Bangor (Gwynedd and Anglesey) · Extensions over a garage across Gwynedd and Anglesey

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