- Postcode district
- CF10
- Survey
- Free for new and replacement doors
- Typical lead time
- Typically 6–8 weeks for slimline systems after check survey sign-off
- Guide price
- From £5,095 inc VAT
- Nearby
- Penarth, Dinas Powys, Caerphilly
- Building rules
- Wales
What sliding doors for extensions offer homes in Cardiff
A few practical points decide whether sliding doors for extensions suit a particular room and opening:
For a garden room at the bottom of a Cardiff garden, think about access: large glass panels need a clear route from the road to the site.
If your Cardiff builder is about to pour the screed, confirm the finished floor level for the threshold first, because it is very hard to change afterwards.
- Garden rooms benefit from the same approach, with a door sized to the frame and a header designed to carry the roof without pressing down on the door.
- Being involved at drawing stage means the opening is formed to suit the door, rather than the door being compromised to suit an opening built a few centimetres out.
- Slimline aluminium systems with interlocks typically around 20–25 mm maximise the glass in a new rear wall, keeping the view as open as possible.
Sunlight, glass and orientation in Cardiff
In Cardiff the shortest day has roughly 7 h 50 min of daylight and the longest about 16 h 38 min. The noon sun sits near 15° above the horizon in winter and 62° in summer — so glass that faces south collects useful warmth from October to March, while a west-facing door may need solar control to stop it overheating in July.
Sliding doors for extensions and garden rooms prices in Cardiff
These are guide prices for fitted doors, including VAT. They run from an entry-level system to a premium one at the same size; the survey confirms which suits your opening.
| Overall width | Typical panels | Guide price (fitted, inc VAT) |
|---|---|---|
| 2.1 m | 2 panels | £5,495–£6,795 |
| 4.8 m | 3 panels | £9,595–£11,695 |
| 6.0 m | 4 panels | £11,395–£13,895 |
See every size on the sliding doors for extensions page or try the guide price tool.
What happens when you order sliding doors for extensions in Cardiff?
A surveyor visits your Cardiff home to check the wall, the structure above and the floor levels, and talks through glass and finish. Any building work is planned to the engineer's design, the door is made to the finished opening sizes — typically 6–8 weeks for slimline systems after check survey sign-off — and fitting usually takes 1–2 days, scheduled to the build programme.
Do you need approval in Cardiff?
In Wales, sliding doors in an extension are approved as part of the extension's Building Regulations application, and the glazing must meet the Welsh energy and safety glazing requirements, including the limits on how much of an extension can be glazed.
Options to consider for your sliding door for an extension
- Flush threshold. A level floor from inside to out, with a drainage channel set into the patio.
- Triple glazing. For low-energy extensions or north-facing walls, subject to panel size limits.
- Corner opening. Sliding panels meeting at a corner with no post, for extensions open on two sides.
Questions about sliding doors for extensions in Cardiff
Do you fit sliding doors for extensions in Cardiff?
Yes. We survey and fit sliding doors for extensions in Cardiff and across South Glamorgan, including nearby Penarth and Dinas Powys. Start with a guide price online or call us, and we will arrange a free survey for a new or replacement door.
What sliding doors suit a garden room?
A garden room usually suits a two-panel or three-panel sliding door sized to the front of the building, with a header strong enough to carry the roof without pressing on the frame. Aluminium systems are a common choice because they are stable and need little maintenance. Glass with good insulation helps if the room will be used all year.
When should I order sliding doors for an extension?
Order sliding doors for an extension as soon as the opening is built and a check survey can be done, and agree the target fitting date with your builder in advance. Slimline doors typically take 6–8 weeks to make after sign-off. Getting a quote from drawings early means the specification is settled and only the final measurements are needed.
How much do sliding doors for an extension cost?
Slimline sliding doors for an extension have a guide price of £7,795–£9,495 for a 3.6 m opening and £9,595–£11,695 for a 4.8 m opening, fitted, inc VAT at standard 2.1 m height. Taller doors, extra panels, special glass and flush thresholds move the price. Your written quote after the check survey fixes it.

