Caerphilly, South Wales Valleys
Side return extension in Caerphilly
Thinking about a side return extension in Caerphilly? Infilling the narrow passage beside a Victorian or Edwardian back addition. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.
Caerphilly sits in the South Wales Valleys, with postcode districts including CF83. In Caerphilly we check the boundary line and the neighbour's gutter before drawing a side return, because a few centimetres decide whether the wall goes on or beside the boundary.
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 side return extension cost in Caerphilly?
Guide prices for a side return extension in Caerphilly start from our Wales rate of £2,140–£3,530 per square metre, including VAT. 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 for a side return extension in Caerphilly?
Whether your side return extension in Caerphilly needs a planning application depends on its size, your house and any local restrictions.
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. At the first visit we measure what is there now and tell you which route fits: permitted development or a householder planning application.
What are homes in Caerphilly like to extend?
Caerphilly is largely terraced streets on sloping ground, where back gardens step up or down from the house. Excavation, retaining walls and drainage are priced at the survey.
How a side return extension in Caerphilly 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.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
Written price, then build
Once the design and approvals are in place, you get a fixed written price and programme, and we build through to sign-off.
Side return extensions near Caerphilly
From Caerphilly, the nearest places we also cover are Rhiwbina (3.2 miles) and Whitchurch (4.3 miles).
- Side return extension in Rhiwbina
- Side return extension in Whitchurch
- Side return extension in Risca
- Side return extension in Pontypridd
- Side return extension in Nelson
Other work in Caerphilly:
FAQ
Side return extension questions in Caerphilly
Can I get a price without a visit?
Our online guide-price tool gives a range in a couple of minutes. A written price needs a survey.
How much does a side return extension cost in Caerphilly?
As a guide, £2,140–£3,530 per square metre including VAT for a standard specification. For example, 2 m wide × 6 m deep (12 m²): about £25,500–£42,500 at that rate. Your written price follows the survey.
Is a side return permitted development?
Sometimes, as a side extension within the width and height limits, but not in conservation areas, and many terraces are in one.
Can you match the brick or stone on my Caerphilly house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
What postcode areas do you cover around Caerphilly?
Including CF83, and the surrounding South Wales Valleys area.
Do I need planning permission for a rear extension in Caerphilly?
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.