Llantrisant · Mid Glamorgan

Kitchen extensions with bedrooms above in Llantrisant

Adding a kitchen extension with bedrooms above in Llantrisant gives you two new rooms stacked on one footprint. Here's how we'd approach it, what it typically costs and the rules that apply in Wales.

Before you start in Llantrisant, here's what applies.

Postcode districts
CF72
County / area
Mid Glamorgan, Wales
Price region
Wales
Guide price
£51,500–£69,500 (£1,840–£2,480 per m²), kitchen units and worktops priced separately
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.
Nearest towns
Beddau (1.2 miles), Pontyclun (1.5 miles), Llanharan (2.8 miles)
Distance to Rhondda
about 8.8 miles
First visit
Free, no obligation

About a kitchen extension with bedrooms above

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.

We cover postcode district CF72 in and around Llantrisant, along with neighbouring Beddau, Pontyclun and Llanharan.

What it costs in Llantrisant

Using our Wales rates, a kitchen extension with bedrooms above with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space) comes to about £51,500–£69,500 (kitchen units and worktops priced separately), including VAT. Bigger or more glazed designs cost more per m². The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.

SpecPer m²A 4 m × 3.5 m footprint on two floors (28 m² of new floor space)
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

Planning and building regulations in Llantrisant

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).

Design points for Llantrisant homes

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'd run your project

  1. Visit and first ideas

    One of our team visits your house in Llantrisant, checks the walls, roof and drains, and sketches out options with you.

  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. Price it properly

    Once the engineer's calculations are in, we fix the build price in writing, with a clear list of what's included.

  4. Finish and certify

    Second fix, plastering and making good, then building control's final inspection and the completion paperwork.

Questions about kitchen extensions with bedrooms above in Llantrisant

How much does a kitchen extension with bedrooms above cost in Llantrisant?

Our guide for Wales, which covers Llantrisant, is £1,840–£2,480 per m² including VAT. A typical project with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space) comes to about £51,500–£69,500 (kitchen units and worktops priced separately). Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Do I need planning permission for a kitchen extension with bedrooms above in Llantrisant?

Llantrisant is in Wales, so Wales planning rules apply. 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. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

Who handles building regulations for a project in Llantrisant?

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.

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 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.

Nearby

We also cover places near Llantrisant, including:

Other extensions in Llantrisant

All two-storey extension services in Llantrisant · Kitchen extensions with bedrooms above across Mid Glamorgan

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