- Postcode district
- CT6
- 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
- Whitstable, Canterbury, Faversham
- Building rules
- England
Why choose sliding doors for extensions in Herne Bay?
A few practical points decide whether sliding doors for extensions suit a particular room and opening:
When your Herne Bay extension is going through Building Control, keep the energy information for the doors to hand, as the inspector may ask for it.
For a garden room at the bottom of a Herne Bay garden, think about access: large glass panels need a clear route from the road to the site.
- 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.
- 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 Herne Bay and what it means for your glass
Daylight in Herne Bay runs from about 7 h 51 min in December to 16 h 37 min in June, with the noon sun at roughly 15° and 62° respectively. Use that to choose your glass: standard low-E double glazing for north and east elevations, and consider solar-control or triple glazing for sunny south and west walls.
How much do sliding doors for extensions cost in Herne Bay?
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) |
|---|---|---|
| 4.0 m | 3 panels | £8,395–£10,195 |
| 4.8 m | 3 panels | £9,595–£11,695 |
| 6.0 m | 4 panels | £11,395–£13,895 |
See every size on the sliding doors for extensions page or try the guide price tool.
Timescales for sliding doors for extensions in Herne Bay
Here is the usual sequence in Herne Bay: 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 Whitstable, Canterbury and Faversham.
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.
Finishes and extras for sliding doors for extensions
- Three or four panels. More panels for wider extension openings, with one or more sliding.
- Corner opening. Sliding panels meeting at a corner with no post, for extensions open on two sides.
- Two-panel slimline. One sliding and one fixed panel, suiting openings up to around 3.6 m depending on the system.
Questions about sliding doors for extensions in Herne Bay
Do you fit sliding doors for extensions in Herne Bay?
Yes. We survey and fit sliding doors for extensions in Herne Bay and across Kent, including nearby Whitstable and Canterbury. Start with a guide price online or call us, and we will arrange a free survey for a new or replacement door.
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.
How much do sliding doors for an extension cost?
Slimline sliding doors for an extension have a guide price of £7,795–£9,495 for a 3.6 m opening and £9,595–£11,695 for a 4.8 m opening, fitted, inc VAT at standard 2.1 m height. Taller doors, extra panels, special glass and flush thresholds move the price. Your written quote after the check survey fixes it.
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.

