- Postcode district
- NW4
- 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
- Golders Green, Finchley, Mill Hill
- Building rules
- England
What sliding doors for extensions offer homes in Hendon
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 Hendon garden, think about access: large glass panels need a clear route from the road to the site.
If your Hendon 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.
- We provide the structural opening size and fitting tolerances in writing, giving your builder a clear target and avoiding disputes about who measured what.
- 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.
Planning glass for the light in Hendon
At the latitude of Hendon, the midday sun climbs to about 62° in late June but only about 15° in late December, when daylight lasts around 7 h 49 min against 16 h 39 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 Hendon?
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 Hendon 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.
Timescales for sliding doors for extensions in Hendon
A surveyor visits your Hendon 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 Hendon?
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.
Choosing the specification
- 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.
- Three or four panels. More panels for wider extension openings, with one or more sliding.
Questions about sliding doors for extensions in Hendon
Do you fit sliding doors for extensions in Hendon?
Yes. We survey and fit sliding doors for extensions in Hendon and across Greater London, including nearby Golders Green and Finchley. Start with a guide price online or call us, and we will arrange a free survey for a new or replacement door.
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.
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.

