Kitchen Extension Cost in Cardiff: 2026 Price Guide
08 Aug 2026
Cardiff grew explosively in the late 19th and early 20th centuries as the world's largest coal-exporting port, and the dense Victorian terraces built to house that workforce - across Roath, Cathays and Pontcanna - are still the dominant housing type in the inner city today. Extending one of these terraces is a genuinely different job from a house in Llandaff or the leafier western suburbs, both in plot size and access.
| Extension size | Typical cost |
|---|---|
| Small (up to 15m²) | £18,500-£32,500 |
| Medium (15-25m²) | £32,500-£51,000 |
| Large (25m²+) | £51,000 upwards |
Wales has its own planning rules
Wales has had its own planning legislation, separate from England's, since the Planning (Wales) Act 2015 - permitted development thresholds and processes differ from England, so an England-focused extension guide won't reliably apply. Always check directly with Cardiff Council's planning service before finalising a design.
What drives cost in Cardiff specifically
Access on Roath and Cathays' narrower terraced streets is a recurring factor, much as in any Victorian terraced city - many streets are too tight for a skip without a council permit. Properties near Llandaff Cathedral or within Pontcanna's conservation area typically face closer scrutiny of materials and roofline, which can push costs up even for a modest extension.
Ready to get quotes? Post your job on builderfinder.uk and hear from vetted, reviewed builders who cover Cardiff - it's free, and your details stay private until you accept one.
Builders in Cardiff
See all builders in Cardiff →Find a trade in Cardiff
Frequently asked questions
How much does a kitchen extension cost in Cardiff?
A small extension (up to 15m²) runs £18,500-£32,500, a medium one (15-25m²) £32,500-£51,000, and a larger extension £51,000 upwards.
Does England's planning guidance apply to a Cardiff kitchen extension?
No - Wales has had its own planning legislation since the Planning (Wales) Act 2015, with different permitted development thresholds, so always check directly with Cardiff Council.
Ready to get started?