Caerphilly, South Wales Valleys
Glazed rear extension in Caerphilly
Glazed rear extension in Caerphilly: full-height glass, slim frames and big rooflights for the most open rear room. We measure the house, show you what the rules allow, price it in writing and build it.
Caerphilly is covered from our South Wales Valleys round, including CF83. If your garden in Caerphilly faces south, expect us to talk about overhangs and solar-control glass before frame colours.
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 glazed rear extension cost in Caerphilly?
For Caerphilly we work from the Wales rate: £2,600–£4,460 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 |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £31,000–£53,500 |
| 4 m wide × 6 m deep (24 m²) | £62,500–£107,000 |
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 glazed rear extension in Caerphilly?
Planning for a glazed rear extension in Caerphilly follows the Welsh householder rules.
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.
Wales has its own Approved Document L, with targets for walls, roofs, floors and glazing similar to but not identical with England's. Heavily glazed designs are checked with a calculation.
Conservation areas, National Parks and National Landscapes restrict permitted development in Wales, and listed buildings need listed building consent. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.
What are homes in Caerphilly like to extend?
Stone terraces along the valley floors and post-war semis higher up are typical of Caerphilly. Sloping sites are common, so floor levels and retaining walls are designed at the start.
How a glazed rear extension in Caerphilly 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.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
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.
Glazed rear extensions near Caerphilly
Neighbouring places we cover include Rhiwbina (3.2 miles) and Whitchurch (4.3 miles).
- Glazed rear extension in Rhiwbina
- Glazed rear extension in Whitchurch
- Glazed rear extension in Risca
- Glazed rear extension in Pontypridd
- Glazed rear extension in Nelson
Other work in Caerphilly:
FAQ
Glazed rear extension questions in Caerphilly
Do you handle building control in Caerphilly?
Yes. We apply to the council or a registered approver under the Welsh regulations and hand over the completion certificate.
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.
Does glass need planning permission?
The same rules apply as any rear extension; glass does not change the depth or height limits.
How much does a glazed rear extension cost in Caerphilly?
As a guide, £2,600–£4,460 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £31,000–£53,500 at that rate. Your written price follows the survey.
Who will build my extension?
Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.
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.