- Postcode district
- SA31
- 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
- Llanelli, Ammanford, Gorseinon
- Building rules
- Wales
Sliding doors for extensions and garden rooms in Carmarthen: what to know
Most homeowners choosing sliding doors for extensions want the same things: more light, a clear view and a door that is easy to live with.
Planning an extension in Carmarthen? Send us the drawings before the steel is ordered, so the beam above the doors can be designed with the door in mind.
Where an extension in Carmarthen faces south or west, ask about solar-control glass, because a wall of glass in a single-storey room can overheat in summer.
- We provide the structural opening size and fitting tolerances in writing, giving your builder a clear target and avoiding disputes about who measured what.
- Agreeing a fitting date with your builder lets the extension be made weathertight on programme, so plastering and flooring can follow without waiting on the doors.
- Setting the finished floor level before the screed goes down allows a low threshold, typically 15–25 mm, or a flush one with a drainage channel outside.
Planning glass for the light in Carmarthen
At the latitude of Carmarthen, the midday sun climbs to about 62° in late June but only about 15° in late December, when daylight lasts around 7 h 46 min against 16 h 42 min in midsummer. A south-facing sliding door for an extension lets that low winter sun deep into the room; on a west or south elevation, solar-control glass keeps summer afternoons comfortable.
How much do sliding doors for extensions cost in Carmarthen?
The table shows guide prices for common sizes, supplied and fitted, including VAT. Your exact price is fixed in a written quote once the opening in your Carmarthen home has been measured.
| Overall width | Typical panels | Guide price (fitted, inc VAT) |
|---|---|---|
| 1.8 m | 2 panels | £5,095–£6,195 |
| 2.1 m | 2 panels | £5,495–£6,795 |
| 4.8 m | 3 panels | £9,595–£11,695 |
See every size on the sliding doors for extensions page or try the guide price tool.
Survey, manufacture and fitting around Carmarthen
Here is the usual sequence in Carmarthen: guide price, free survey, written quote, any building work, then manufacture (typically 6–8 weeks for slimline systems after check survey sign-off). Fitting typically takes 1–2 days, scheduled to the build programme. Nearby, we also survey in Llanelli, Ammanford and Gorseinon.
Do you need approval in Carmarthen?
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
- Triple glazing. For low-energy extensions or north-facing walls, subject to panel size limits.
- Two-panel slimline. One sliding and one fixed panel, suiting openings up to around 3.6 m depending on the system.
- Flush threshold. A level floor from inside to out, with a drainage channel set into the patio.
Questions about sliding doors for extensions in Carmarthen
Is the price different in Carmarthen?
No. Guide prices for sliding doors for extensions are the same across mainland Britain, including Carmarthen. The fitted price depends on size, system, glass and finish, and any structural work, all fixed in your written quote after survey.
What structural opening size should my builder leave for sliding doors?
Your builder should leave the structural opening size we give in writing for your chosen door, which is the frame size plus a small fitting tolerance on each side and at the head. The exact figure depends on the system and the threshold detail. We confirm it from your drawings early, then check the built opening before the door is made.
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.
How do I get a level threshold in an extension?
A level or flush threshold in an extension needs the finished floor level inside to be set relative to the door sill and the outside paving before the screed goes down. Outside, a drainage channel is needed across the threshold so rain cannot run in. Our thresholds guide explains the options.