Cardiff and the Vale
Side return extensions in Cardiff and the Vale
Infilling the narrow passage beside a Victorian or Edwardian back addition. Rear extensions in Cardiff and the Vale: we cover 6 towns including Cardiff, Barry and Penarth, with design, approvals and the build under one contract.
Side return projects in Cardiff usually start with a drainage survey of the side passage. Cardiff and the Vale 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 side return extension cost in Cardiff and the Vale?
In Cardiff and the Vale, our guide for a side return extension is £2,140–£3,530 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 |
|---|---|
| 2 m wide × 6 m deep (12 m²) | £25,500–£42,500 |
| 2.5 m wide × 7 m deep (17.5 m²) | £37,500–£62,000 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission in Cardiff and the Vale?
In Wales a single-storey side extension can be permitted development if it is no more than 4 metres high and the house ends up no more than 50% wider than the original. Many side return infills on terraced streets, and most wraparounds, go through a householder application.
The Party Wall etc. Act 1996 also applies in Wales: two months' notice for work to a shared wall and one month for foundations dug close to a neighbour's building.
Conservation areas, National Parks and National Landscapes restrict permitted development in Wales, and listed buildings need listed building consent.
Where in Cardiff and the Vale do we work?
FAQ
Questions people ask
How much space does a side return add?
Typically 8 to 18 square metres, enough to turn a galley kitchen into a kitchen-diner with an island.
Do I need my neighbour's permission?
Not their permission, but in England and Wales you must serve party wall notices, and a neighbour can consent in writing or ask for a surveyor's award.
Can I combine a side return with a rear extension?
Yes; that is a wraparound extension, and it gives the biggest open-plan room a terrace can have.
Do you cover all of Cardiff and the Vale?
We cover 6 towns and districts in Cardiff and the Vale, including Cardiff, Barry and Penarth.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.