- Postcode district
- W8
- 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
- Notting Hill, Chelsea, Hammersmith
- Building rules
- England
Sliding doors for extensions and garden rooms in Kensington: 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.
For a garden room at the bottom of a Kensington garden, think about access: large glass panels need a clear route from the road to the site.
When your Kensington 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.
- 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.
Daylight in Kensington and what it means for your glass
In Kensington 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.
What should you budget for sliding doors for extensions in Kensington?
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 Kensington 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 |
| 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.
Timescales for sliding doors for extensions in Kensington
Here is the usual sequence in Kensington: 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 Notting Hill, Chelsea and Hammersmith.
Rules for sliding doors for extensions in England
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.
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.
- Corner opening. Sliding panels meeting at a corner with no post, for extensions open on two sides.
- Solar-control glass. Coated glass for south- and west-facing extensions prone to summer overheating.
Questions about sliding doors for extensions in Kensington
Do I need building approval for sliding doors for extensions in Kensington?
In England a replacement door is a controlled fitting, so compliance is arranged through a competent person scheme installer or Building Control; new openings need a Building Regulations application. We confirm the right route for your property at survey, so the paperwork is in place before fitting.
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.
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 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.