Penarth, Cardiff and the Vale
Two-storey rear extension in Penarth
A larger kitchen downstairs and an extra bedroom or bathroom upstairs, under one roof. If you live in Penarth and want to know what a two-storey rear extension would cost and whether it needs planning, start with the online guide price or a free site visit.
Penarth sits in Cardiff and the Vale, with postcode districts including CF64. Two-storey rear extensions suit semi-detached houses in Penarth best, where the extra bedroom matters as much as the bigger kitchen.
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 two-storey rear extension cost in Penarth?
For Penarth we work from the Wales rate: £1,670–£2,510 per square metre of new floor, including VAT, standard specification. Prices in Wales sit below our West Midlands baseline; sloping sites are the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m × 5 m footprint, two floors (30 m²) | £50,000–£75,500 |
| 4 m × 6 m footprint, two floors (48 m²) | £80,500–£120,500 |
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 two-storey rear extension in Penarth?
Whether your two-storey rear extension in Penarth needs a planning application depends on its size, your house and any local restrictions.
In Wales a rear extension of more than one storey can be permitted development if the ground floor projects no more than 4 metres and the upper floor no more than 3 metres, with at least 10.5 metres to the rear boundary. It is not permitted development in conservation areas, National Parks or National Landscapes, so many double-storey schemes need a householder application.
Conservation areas, National Parks and National Landscapes restrict permitted development in Wales, and listed buildings need listed building consent. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.
What are homes in Penarth like to extend?
Penarth 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 two-storey rear extension in Penarth comes together
Free site visit
We measure the house and garden, look at the back wall, drainage and boundaries, and talk through what you want from the space.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
Paperwork handled
Planning or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
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.
Two-storey rear extensions near Penarth
Neighbouring places we cover include Cardiff (2.9 miles) and Whitchurch (5.4 miles).
- Two-storey rear extension in Cardiff
- Two-storey rear extension in Whitchurch
- Two-storey rear extension in Barry
- Two-storey rear extension in Rhiwbina
- Two-storey rear extension in Caerphilly
Other work in Penarth:
FAQ
Two-storey rear extension questions in Penarth
How long does a rear extension take to build in Penarth?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
Do I need planning permission for a rear extension in Penarth?
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.
Can it be built on a terraced house?
Sometimes, but the upper floor is harder to get through planning on a terrace because of the effect on neighbours. A single-storey extension with a loft conversion is often an easier route.
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.
Is the site visit in Penarth free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
Can you match the brick or stone on my Penarth house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.