Cardiff and the Vale of Glamorgan · Wales

Kitchen extensions with bedrooms above in Cardiff and the Vale of Glamorgan

If you're in Cardiff and the Vale of Glamorgan and weighing up a kitchen extension with bedrooms above, start here: guide costs for Wales, the approvals you'll need and how we work.

Cardiff and the Vale of Glamorgan at a glance

Nation
Wales
Price region
Wales
Postcode areas
CF
Towns covered
10 listed below, plus surrounding villages
Approval route
It may be permitted development if the ground floor goes no more than 4 m and the first floor no more than 3 m beyond the original rear wall, with the first floor 10.5 m from the rear boundary.
Site visits
Free, no obligation

What a kitchen extension with bedrooms above involves

A kitchen extension with bedrooms above is a two-storey extension designed so the ground floor becomes a larger, usually open-plan kitchen and dining space, with one or two bedrooms or a bathroom on the first floor. It is a natural fit for a two-storey rear extension. The key design issues are the steel beams that open up the house, glazing and ventilation.

The main places we list in Cardiff and the Vale of Glamorgan are Cardiff (CF10), Barry (CF62), Penarth (CF64), Llantwit Major (CF61), Whitchurch (Cardiff and the Vale of Glamorgan) (CF14) and Rhiwbina (CF14). We cover the villages in between too.

Guide price in Wales

Our guide for Wales is £1,840–£2,480 per m² including VAT. On a project with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space), that puts a kitchen extension with bedrooms above in Cardiff and the Vale of Glamorgan at roughly £51,500–£69,500 (kitchen units and worktops priced separately). Design fees, structural calculations and approval fees are separate and listed on our prices page.

SpecPer m²Typical project
Essential£1,690–£2,290 per m²£47,500–£64,000
Standard£1,840–£2,480 per m²£51,500–£69,500
Premium£2,210–£2,980 per m²£62,000–£83,500

Rules in Wales

In Wales, a kitchen extension with bedrooms above can be permitted development if the kitchen goes no more than 4 m and the first floor no more than 3 m beyond the original rear wall, with the first floor 10.5 m from the rear boundary. This lets the kitchen project further than the bedrooms. Otherwise a householder application costs £585.

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).

The Party Wall etc. Act 1996 applies in Wales, so notices may be needed for work on or near a shared wall or boundary.

Getting the design right

Services and drainage

Sinks, dishwashers and an upstairs bathroom all need waste routes to the drains, often near where the extension goes. We check the drains early and plan soil stacks, gas and electrical supplies so the kitchen layout is not limited later.

Steel beams and the open-plan opening

Removing the old rear wall to make one large room means a steel beam, sometimes several, to carry the first floor and roof. The engineer sizes the steel and its supports, and we decide early whether you want a flush ceiling with the beam hidden or a downstand, as this affects ceiling heights.

How we work in Cardiff and the Vale of Glamorgan

  1. Free site visit

    We visit your home in Cardiff and the Vale of Glamorgan, look at the structure, access and boundaries, and talk through what you want the new rooms to do.

  2. Choose the approval route

    Some designs fit permitted development, most need a householder application. We decide which applies in Wales before drawing in detail.

  3. Structure and building control

    A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.

  4. Build and sign-off

    Vetted teams working under S&K build the extension, and we arrange the building control completion certificate at the end.

Towns we cover in Cardiff and the Vale of Glamorgan

Kitchen extensions with bedrooms above in Cardiff and the Vale of Glamorgan: questions

How much does a kitchen extension with bedrooms above cost in Cardiff and the Vale of Glamorgan?

In Wales our guide is £1,840–£2,480 per m² including VAT, so about £51,500–£69,500 (kitchen units and worktops priced separately) for a 4 m × 3.5 m footprint on two floors (28 m² of new floor space). Essential and Premium specs move that by roughly 8% down or 20% up.

Can the kitchen be bigger than the bedrooms above it?

Yes. With planning permission, the ground floor can extend further than the first floor, giving a part single, part two-storey design. In Wales, permitted development allows the ground floor to go 4 m and the first floor 3 m beyond the original rear wall. We show both options at the design stage.

Is it cheaper to build a kitchen extension and bedrooms at the same time?

Yes, in most cases. Building both floors at once means one set of foundations, one roof, one scaffold and one set of approvals. Adding a first floor later means removing the original roof, possibly strengthening the foundations and disrupting the kitchen again. If you think you will need the bedroom, build it now.

Can I keep using my kitchen during the build?

For part of it. The new structure can be built while your existing kitchen stays in use, but when the rear wall is opened and the new kitchen is fitted there will be several weeks without one. We plan when this happens and help you set up a temporary kitchen elsewhere in the house.

Will I need planning permission in Cardiff and the Vale of Glamorgan?

Cardiff and the Vale of Glamorgan is in Wales. It may be permitted development if the ground floor goes no more than 4 m and the first floor no more than 3 m beyond the original rear wall, with the first floor 10.5 m from the rear boundary.

Neighbouring areas

All extension services in Cardiff and the Vale of Glamorgan · About kitchen extensions with bedrooms above

Ready to see what a second storey could do for your home?

Book a free site visit. We'll look at your house, talk through options and explain the approvals you'd need, then price the design stage in writing.

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