- Postcode district
- NW7
- Survey
- Free for new and replacement doors
- Typical lead time
- Typically 4–6 weeks for aluminium, 6–8 weeks for slimline or lift and slide corners, from survey sign-off
- Guide price
- From £8,695 inc VAT
- Nearby
- Edgware, Finchley, Hendon
- Building rules
- England
Corner sliding doors in Mill Hill: what to know
Before you settle on a door type, it helps to know what corner sliding doors do well and what to check before you order.
Where steel for a Mill Hill corner extension would bear on a shared wall, the Party Wall etc. Act 1996 (England and Wales) may apply, so it is worth raising with neighbours early.
Corner glazing changes how a Mill Hill home looks from neighbouring gardens, so confirm the planning position for the extension with your designer or the local planning authority before ordering.
- With no post at the corner, sliding both sets of panels back opens the meeting point of two walls completely, so the room spills straight onto the patio.
- Daylight reaches the room from two directions, which keeps a deep extension brighter through the day as the sun moves round the house.
- When closed, the two corner panels interlock and lock together, so the glass corner stays weathertight and secure without a visible column.
Daylight in Mill Hill and what it means for your glass
Because Mill Hill sees long summer days (about 16 h 40 min) and short winter ones (about 7 h 48 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.
Corner sliding doors prices in Mill Hill
These figures are for the door supplied and fitted, with the engineer's structural calculations, including VAT. The steelwork that supports the corner is designed by the engineer and priced after survey, because it depends on the building. Your price is fixed in a written quote after survey.
| Overall width | Typical panels | Guide price (fitted, inc VAT) |
|---|---|---|
| 3.6 m | 4 panels | £9,595–£11,795 |
| 4.0 m | 4 panels | £10,295–£12,495 |
| 8.0 m | 6 panels | £16,495–£20,095 |
See every size on the corner sliding doors page or try the guide price tool.
How fitting works in Mill Hill
Surveys in the NW7 district are booked at a time that suits you. Once the opening is ready and measured, manufacture is typically 4–6 weeks for aluminium, 6–8 weeks for slimline or lift and slide corners, from survey sign-off; on fitting day the frame is set level and sealed, and the panels are adjusted so they glide properly. Fitting usually takes 1–2 days for the door, after 3–5 days of structural building work.
Rules for corner sliding doors in England
A new or wider opening in England needs Building Control approval for the structural work as well as compliance for the door itself under Approved Documents L and K. Expect structural calculations, a steel beam and, where a party wall is involved, notices under the Party Wall etc. Act 1996.
Options to consider for your corner sliding door
- Threshold. Standard, low or flush thresholds, with drainage detailed along both elevations.
- Panel layout. Two panels per side for smaller corners or three per side for wider ones, with fixed panels at the far ends.
- Colours. Single or dual colour powder coating, so the outside can match the extension cladding or render.
Questions about corner sliding doors in Mill Hill
Do you fit corner sliding doors in Mill Hill?
Yes. We survey and fit corner sliding doors in Mill Hill and across Greater London, including nearby Edgware 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 I add a corner sliding door to an existing house?
A corner sliding door can be added to an existing house, but it is a structural project rather than a door swap: the corner of the building has to be rebuilt with engineered steel to carry the load where the post or wall used to be. It is usually done as part of an extension or rear remodel, and a survey plus an engineer's assessment confirm what the structure above needs.
Do corner sliding doors lose more heat?
Corner sliding doors lose heat in proportion to their glazed area, so a large glass corner loses more than a solid wall would, but thermally broken systems keep typical whole-door U-values around 1.2–1.6 W/m²K double glazed. In England, a new door in an existing home with more than 60% glazing must achieve 1.4 W/m²K or better, and triple glazing is available. Wales, Scotland and Northern Ireland apply their own energy rules.
Is the open corner a weak point for security?
The corner of a corner sliding door is not a weak point when the system is properly specified, because the two meeting panels interlock and lock together, typically with multi-point hardware at the corner as well as on the sliding edges. Laminated glass adds resistance to breaking through. Corner systems are available tested to PAS 24, and the locking specification is confirmed in your quote.