Newport and Monmouthshire
Rear extensions for detached houses in Newport and Monmouthshire
Wider, deeper rear extensions with room for vaulted roofs and big glazing. We design and build rear extensions across Newport and Monmouthshire, from Newport and Abergavenny to Chepstow, covering single-storey kitchen extensions, two-storey additions, side returns and wraparounds.
Newport and Monmouthshire 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 much does a detached house rear extension cost in Newport and Monmouthshire?
For Newport and Monmouthshire we work from the Wales rate: £1,810–£2,980 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 |
|---|---|
| 4 m wide × 6 m deep (24 m²) | £43,500–£71,500 |
| 5 m wide × 8 m deep (40 m²) | £72,500–£119,000 |
Ground conditions, glazing, the roof and how far the house is opened up move the final figure within the range.
Do you need planning permission in Newport and Monmouthshire?
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 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.
Where in Newport and Monmouthshire do we work?
FAQ
Questions people ask
Can I have a vaulted ceiling?
Yes, with a pitched roof and exposed or boxed rafters, subject to the height limits.
Is an oak frame worth it?
It is a premium finish with a long life; it costs more than blockwork with a plain roof.
Do I need party wall notices?
Only if the extension is close enough to a neighbour's building for the excavation rules to apply.
Do you cover all of Newport and Monmouthshire?
We cover 6 towns and districts in Newport and Monmouthshire, including Newport, Abergavenny and Chepstow.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.