Llantrisant, South Wales Valleys
Side return extension in Llantrisant
Infilling the narrow passage beside a Victorian or Edwardian back addition. We design, get the approvals for and build side return extensions in Llantrisant and the surrounding area, with one contract from the first survey to building control sign-off.
Llantrisant and its postcode districts CF38 and CF72 are part of our South Wales Valleys coverage. In Llantrisant 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 Llantrisant?
A side return extension in Llantrisant is priced at £2,140–£3,530 per square metre including VAT as a guide, before kitchen fit-out and fees. 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 |
We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.
Do you need planning permission for a side return extension in Llantrisant?
Planning for a side return extension in Llantrisant follows the Welsh householder rules.
Welsh side-extension rules limit a single-storey side addition to 4 metres high and a 50% increase in the width of the original house, with tighter limits in conservation areas. Wraparounds usually need a planning application.
In Wales, as in England, the Party Wall etc. Act 1996 requires notice to neighbours before work to a shared wall or excavation near their foundations.
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 Llantrisant like to extend?
Stone terraces along the valley floors and post-war semis higher up are typical of Llantrisant. Sloping sites are common, so floor levels and retaining walls are designed at the start.
How a side return extension in Llantrisant 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.
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.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.
Side return extensions near Llantrisant
Neighbouring places we cover include Pontypridd (4.5 miles) and Tonypandy (6.6 miles).
- Side return extension in Pontypridd
- Side return extension in Tonypandy
- Side return extension in Whitchurch
- Side return extension in Rhiwbina
- Side return extension in Caerphilly
Other work in Llantrisant:
FAQ
Side return extension questions in Llantrisant
Is the site visit in Llantrisant free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
What postcode areas do you cover around Llantrisant?
Including CF38 and CF72, and the surrounding South Wales Valleys area.
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.
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.
How much does a side return extension cost in Llantrisant?
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.
Do you handle building control in Llantrisant?
Yes. We apply to the council or a registered approver under the Welsh regulations and hand over the completion certificate.