Cardiff and the Vale of Glamorgan · Wales

Design and build two-storey extensions in Cardiff and the Vale of Glamorgan

Planning an extension in Cardiff and the Vale of Glamorgan? This is how our design and build service works, with the Wales rules and typical fees.

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
Site visits
Free, no obligation

What a design and build project involves

A design and build project for a two-storey extension involves one team taking responsibility for the whole job: the survey, design, planning or permitted development, structural engineering, building regulations, party wall matters where they apply and the construction itself. You deal with one point of contact instead of coordinating an architect, engineer and builder separately. The design stage is priced first, then the build at a fixed price.

Cardiff and the Vale of Glamorgan towns we list: Cardiff (CF10), Barry (CF62), Penarth (CF64), Llantwit Major (CF61), Whitchurch (Cardiff and the Vale of Glamorgan) (CF14) and Rhiwbina (CF14). Every other address in Cardiff and the Vale of Glamorgan is covered as well.

Fees

The design stage is priced in writing before it starts, and the build is a fixed price in writing once the design is agreed.

Rules in Wales

In Wales, design and build covers the Welsh permitted development tests or a householder application (£585), building regulations approval under the Welsh Approved Documents and Party Wall Act notices where needed. We follow the Welsh rules, which allow more under permitted development and differ on energy efficiency.

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

Cost checking as you design

Because the people drawing the extension also build it, each design option comes with a guide cost. That avoids the common problem of an approved design that turns out to be too expensive once builders price it.

How the stages work

We start with a free site visit, then a design stage priced in writing before it begins. That covers the survey, design, approvals, structural design and building regulations. Once the design is agreed, the build price is fixed in writing before work starts.

How we work in Cardiff and the Vale of Glamorgan

  1. Measure and listen

    A visit to Cardiff and the Vale of Glamorgan to understand how you live in the house now and what the extra rooms need to do, plus a first look at the structure.

  2. Plans, then approval

    Measured survey, design, then the right approval route for your house. We explain each step before we take it.

  3. Detail and price

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

  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

Design and build two-storey extensions in Cardiff and the Vale of Glamorgan: questions

What is the difference between design and build and using an architect?

With an architect, you appoint them for the design and approvals, then find and manage a builder separately. With design and build, one team does both, so cost, buildability and approvals are considered together and there is one point of contact. Some people still prefer to hire an architect separately.

Who builds my extension?

Your extension is built by vetted teams working under S&K, with the project managed by us from design to completion. You have one point of contact throughout, and the same team that prepared the design is responsible for the build.

Do I have to use you for the build if I pay for the design stage?

No. The design stage is priced separately, so you can take the approved drawings to other builders if you choose. Most people who use design and build carry on to the build, because the design has been costed as it developed.

Neighbouring areas

All extension services in Cardiff and the Vale of Glamorgan · About design and build two-storey extensions

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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