- Postcode district
- CR4
- 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
- Morden, Tooting, Wimbledon
- Building rules
- England
Are sliding doors for extensions right for your Mitcham home?
The right door depends on the opening, the room and the way you use the garden. Here is how sliding doors for extensions tend to work out in practice:
For a garden room at the bottom of a Mitcham garden, think about access: large glass panels need a clear route from the road to the site.
When your Mitcham extension is going through Building Control, keep the energy information for the doors to hand, as the inspector may ask for it.
- Telling the engineer the door type and span early lets them design the beam above it to limit deflection, protecting the smooth running of large sliding panels.
- 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.
- 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.
Daylight in Mitcham and what it means for your glass
Because Mitcham sees long summer days (about 16 h 37 min) and short winter ones (about 7 h 51 min), the elevation your door faces makes a real difference. With the midday sun at about 15° in winter, a south-facing door brings light well into the room; a west-facing door catches hot late-afternoon sun in summer.
Guide prices for sliding doors for extensions in Mitcham
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) |
|---|---|---|
| 1.8 m | 2 panels | £5,095–£6,195 |
| 3.0 m | 2 panels | £6,895–£8,395 |
| 3.6 m | 2 panels | £7,795–£9,495 |
See every size on the sliding doors for extensions page or try the guide price tool.
How fitting works in Mitcham
Here is the usual sequence in Mitcham: 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 Morden, Tooting and Wimbledon.
Do you need approval in Mitcham?
Doors in an English extension go through the extension's Building Regulations approval. Under Approved Document L, the total area of windows, roof windows and doors is normally capped at 25% of the extension's floor area plus any openings the extension removes, unless your designer shows compensating improvements; the glass must be safety glazing under Approved Document K.
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.
- Two-panel slimline. One sliding and one fixed panel, suiting openings up to around 3.6 m depending on the system.
- Corner opening. Sliding panels meeting at a corner with no post, for extensions open on two sides.
Questions about sliding doors for extensions in Mitcham
How soon can you survey in Mitcham?
Surveys in the CR4 district are booked at a time that suits you, and we offer survey dates when we reply to your enquiry. After you approve the written quote, manufacture is typically 6–8 weeks for slimline systems after check survey sign-off.
Can you work with my builder and architect?
Yes, working with your builder, architect and structural engineer is the normal way we approach extension doors. We can provide technical details, opening sizes, threshold requirements and fixing information, and attend site for the check survey. Your builder forms the opening and prepares the floor, and our installers fit the doors to the agreed programme.
Why does the steel beam matter for sliding doors?
The steel beam above an extension's sliding door matters because every beam bends a little under load, and a large sliding door needs a straight, level head to run freely. If the engineer knows a wide slider will sit under the beam, they can design for low deflection. Too much movement can make panels stiff or bind.
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.