- Postcode district
- SM1
- 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
- Carshalton, Morden, Mitcham
- Building rules
- England
Sliding doors for extensions and garden rooms in Sutton: what to know
Before you settle on a door type, it helps to know what sliding doors for extensions do well and what to check before you order.
Self-building in Sutton or elsewhere in Greater London? Ask for the sliding doors to be quoted as part of a wider glazing package so the frames, colours and glass match across the house.
When your Sutton 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.
- 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.
- 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.
Daylight in Sutton and what it means for your glass
Sun angles matter for big glazed doors. Around Sutton, midday sun reaches about 62° in summer and drops to about 15° in winter. That low winter sun is free heat through south-facing glass; high summer sun is easier to shade with a roof overhang, and solar-control glass helps where there is none.
Typical costs for sliding doors for extensions around Sutton
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 Sutton home has been measured.
| Overall width | Typical panels | Guide price (fitted, inc VAT) |
|---|---|---|
| 3.0 m | 2 panels | £6,895–£8,395 |
| 3.6 m | 2 panels | £7,795–£9,495 |
| 4.0 m | 3 panels | £8,395–£10,195 |
See every size on the sliding doors for extensions page or try the guide price tool.
Survey, manufacture and fitting around Sutton
A surveyor visits your Sutton 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 Sutton?
In England, sliding doors in a new extension are covered by the extension's own Building Regulations application rather than a separate door notification. Approved Document L limits the glazed area: windows, roof windows and doors should not normally exceed 25% of the extension's floor area plus the area of any windows or doors lost to the extension, unless the extra glass is compensated for elsewhere. The doors must also meet the energy and safety glazing standards.
Specification choices for sliding doors for extensions in Sutton
- Corner opening. Sliding panels meeting at a corner with no post, for extensions open on two sides.
- Three or four panels. More panels for wider extension openings, with one or more sliding.
- Flush threshold. A level floor from inside to out, with a drainage channel set into the patio.
Questions about sliding doors for extensions in Sutton
Do you fit sliding doors for extensions in Sutton?
Yes. We survey and fit sliding doors for extensions in Sutton and across Greater London, including nearby Carshalton and Morden. Start with a guide price online or call us, and we will arrange a free survey for a new or replacement door.
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.
Can you measure from drawings rather than the built opening?
We can quote from drawings, but we manufacture from a check survey of the built opening, because real openings often differ slightly from the plans. Making a large made-to-measure door from drawings alone risks it not fitting. If a programme makes that unavoidable, any arrangement and who carries the risk would be agreed in writing first.
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.

