- Postcode district
- SL9
- 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
- Chalfont St Peter, Uxbridge, Beaconsfield
- Building rules
- England
Is a sliding door for an extension a good fit for your home in Gerrards Cross?
A few practical points decide whether sliding doors for extensions suit a particular room and opening:
For a garden room at the bottom of a Gerrards Cross garden, think about access: large glass panels need a clear route from the road to the site.
If your Gerrards Cross builder is about to pour the screed, confirm the finished floor level for the threshold first, because it is very hard to change afterwards.
- 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.
- 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.
Sunlight, glass and orientation in Gerrards Cross
In Gerrards Cross the shortest day has roughly 7 h 49 min of daylight and the longest about 16 h 39 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.
Typical costs for sliding doors for extensions around Gerrards Cross
Guide prices are the same across Buckinghamshire. They cover the door supplied and fitted into a prepared opening, including VAT, with options itemised in your quote.
| Overall width | Typical panels | Guide price (fitted, inc VAT) |
|---|---|---|
| 1.8 m | 2 panels | £5,095–£6,195 |
| 3.0 m | 2 panels | £6,895–£8,395 |
| 4.8 m | 3 panels | £9,595–£11,695 |
See every size on the sliding doors for extensions page or try the guide price tool.
How fitting works in Gerrards Cross
Nothing is ordered until you sign off the surveyed specification. The door is made from 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. If you are in Chalfont St Peter or Uxbridge, the same process and prices apply.
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.
Specification choices for sliding doors for extensions in Gerrards Cross
- 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.
- 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 Gerrards Cross
Do you fit sliding doors for extensions in Gerrards Cross?
Yes. We survey and fit sliding doors for extensions in Gerrards Cross and across Buckinghamshire, including nearby Chalfont St Peter and Uxbridge. Start with a guide price online or call us, and we will arrange a free survey for a new or replacement door.
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.
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.
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.

