Conservatory replacement extensions across South Glamorgan
Thinking about a conservatory replacement for your South Glamorgan home? Start with a free site visit: we measure up, check what the council will allow and give you honest guide figures on the day.
- Guide priceFrom £18,500 inc VAT
- PlanningWelsh permitted development rules (rear up to 4 m)
- Towns covered4
- Site visitFree, no obligation

Extensions in and around South Glamorgan
Towns we cover in South Glamorgan include Cardiff, Barry, Penarth, Cowbridge. Welsh housing ranges from stone terraces in the valleys to render-and-slate houses and modern estates, and the Welsh planning rules differ from England's in several places.
Do I need planning permission in South Glamorgan?
In Wales a single-storey rear extension can usually project up to 4 m beyond the rear wall without a planning application, if it is no more than 4 m high, keeps eaves to 3 m and overall height to 4 m within 2 m of a boundary, and covers no more than half the land around the original house. Wales has no larger home extension prior approval scheme.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
Building over or within 3 m of a public sewer needs the water company's consent before the foundations go in.
Building regulations approval is separate from planning. Wales has its own building regulations and approved documents; the council or a registered building control approver checks the plans, inspects the work and issues a completion certificate.
Applications are decided by the local planning authority (your county or county borough council, or the national park authority).
How much does a conservatory replacement cost in South Glamorgan?
For South Glamorgan we adjust our national guide rates by ×0.93, the factor we use for Wales. Figures include VAT; your written quote after the survey replaces them.
Typical rates in South Glamorgan: £1,720 to £3,260 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 3.3 m 10 m² | £18,500 – £22,500 | £19,500 – £26,000 | £25,500 – £33,000 |
| 3.5 m × 4 m 14 m² | £24,000 – £29,000 | £27,500 – £36,000 | £35,500 – £46,000 |
| 4 m × 5 m 20 m² | £34,000 – £41,000 | £39,500 – £51,500 | £51,000 – £65,500 |
Includes removal of the old conservatory. Reusing existing foundations is only possible after investigation.
Try the guide-price tool to see a range for your own size and finish.
Who a conservatory replacement suits
- Conservatories that are too hot or too cold
- Older uPVC conservatories near the end of their life
- Homes where the conservatory sits unused
What happens next
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Common questions in South Glamorgan
Who do I contract with for a conservatory replacement in South Glamorgan?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for South Glamorgan, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
How long does a conservatory replacement take to build in South Glamorgan?
On site, typically 8 to 14 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
Does replacing a conservatory need planning permission?
A solid replacement is treated as a new extension, so it must meet the permitted development limits or get planning permission, and it always needs building regulations approval.
Can I keep the existing base?
Sometimes, but conservatory bases are often too shallow for solid walls. Trial holes tell us before we confirm the price.
Book a free site visit in South Glamorgan
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.