Cardiff and the Vale
Rear extensions in Penarth
Rear extensions in Penarth: single-storey and two-storey extensions, side returns, wraparounds and glass-led designs, planned around older terraces and post-war semis and the Welsh rules.
Penarth is in Cardiff and the Vale, with postcode districts including CF64. The nearest places we also cover are Cardiff (2.9 miles) and Whitchurch (5.4 miles).
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
Rear extensions we build in Penarth
- Single-storey rear extensions
- Two-storey rear extensions
- Kitchen-diner rear extensions
- Side return extensions
- Wraparound extensions
- Glazed and glass-box rear extensions
- Rear extensions for terraced houses
- Rear extensions for semi-detached houses
- Rear extensions for bungalows
- Rear extension plans and planning applications
Also available across Cardiff and the Vale:
- Rear extensions for detached houses
- Flat-roof rear extensions
- Pitched and lean-to roof rear extensions
- Knocking through to a rear extension
- Roof lanterns and rooflights for rear extensions
- Permitted development rear extensions
- Building Regulations for rear extensions
Rear extension prices in Penarth
Prices in Wales sit below our West Midlands baseline; sloping sites are the main variable.
| Example | Guide inc VAT |
|---|---|
| Single-storey, 3 m × 4 m (12 m²) | £21,000–£34,500 |
| Single-storey, 4 m × 6 m (24 m²) | £42,500–£69,000 |
| Two-storey, 3 m × 5 m footprint (30 m²) | £50,000–£75,500 |
| Side return, about 14 m² | £30,000–£49,500 |
| Wraparound, about 25 m² | £51,000–£83,500 |
What are homes in Penarth like to extend?
Older terraces near the centre and post-war semis further out are typical of Penarth. Sloping sites are common in Wales, so floor levels and retaining walls are designed at the start.
Planning rules for Penarth
In Wales a single-storey rear extension can often be permitted development if it projects no more than 4 metres beyond the rear wall and is no more than 4 metres high. Wales has no prior approval route for deeper extensions, so anything bigger needs a householder planning application.
In Wales a rear extension needs Building Regulations approval through the council or a registered approver, and is built to the Welsh Approved Documents, which differ from England's in places, including energy efficiency.
Nearby towns
FAQ
Questions people ask
How much is a rear extension in Penarth?
A 3 m × 4 m single-storey rear extension is about £21,000–£34,500 including VAT at our Wales guide rates; the written price follows a survey.
Do I need planning permission 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.
Is the site visit in Penarth free?
Yes, with no obligation.
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.