Cardiff, Cardiff and the Vale
Terraced house rear extension in Cardiff
Rear and side return extensions for terraces, with access through the house and two neighbours. We design, get the approvals for and build rear extensions for terraced houses in Cardiff and the surrounding area, with one contract from the first survey to building control sign-off.
Cardiff is covered from our Cardiff and the Vale round, including CF3, CF5, CF11 and CF14. On a Cardiff terrace both neighbours usually need party wall notices or agreement, so we talk to them early.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a terraced house rear extension cost in Cardiff?
In Cardiff, our guide for a terraced house rear extension is £1,910–£3,070 per square metre including VAT for a standard specification. Prices in Wales sit below our West Midlands baseline; sloping sites are the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4.5 m deep (13.5 m²) | £25,500–£41,500 |
| 3 m wide × 6 m deep (18 m²) | £34,500–£55,000 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission for a terraced house rear extension in Cardiff?
Whether your terraced house rear extension in Cardiff needs a planning application depends on its size, your house and any local restrictions.
Welsh permitted development allows a single-storey rear extension of up to 4 metres in depth and 4 metres in height, subject to boundary and garden-coverage limits. There is no larger-extension prior approval scheme in Wales.
In Wales, as in England, the Party Wall etc. Act 1996 requires notice to neighbours before work to a shared wall or excavation near their foundations.
Conservation areas, National Parks and National Landscapes restrict permitted development in Wales, and listed buildings need listed building consent. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.
What are homes in Cardiff like to extend?
Cardiff has Victorian terraces near the centre and semis further out. Welsh permitted development allows up to 4 metres at the rear for many houses.
How a terraced house rear extension in Cardiff comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
Fixed price and build
A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.
Terraced house rear extensions near Cardiff
Close by, we work in Whitchurch, about 2.8 miles away, and Penarth, about 2.9 miles away.
- Terraced house rear extension in Whitchurch
- Terraced house rear extension in Penarth
- Terraced house rear extension in Rhiwbina
- Terraced house rear extension in Caerphilly
- Terraced house rear extension in Barry
Other work in Cardiff:
FAQ
Terraced house rear extension questions in Cardiff
Is the site visit in Cardiff free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
Who will build my extension?
Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.
Can you build without side access?
Yes. Materials come through the house in protected runs or over the roof by crane on tight sites.
Do I need planning permission for a rear extension in Cardiff?
Often not for a single-storey rear extension of up to 4 metres under Welsh permitted development. Wales has no prior approval route for deeper extensions.
What postcode areas do you cover around Cardiff?
Including CF3, CF5, CF11, CF14, CF23 and CF24, and the surrounding Cardiff and the Vale area.
Do I need a party wall agreement?
In Wales, usually yes if the extension is on or near a shared boundary or close to a neighbour's foundations. We serve the notices.