- Postcode district
- RH1
- 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
- Reigate, Horley, Coulsdon
- Building rules
- England
Are sliding doors for extensions right for your Redhill home?
A few practical points decide whether sliding doors for extensions suit a particular room and opening:
When your Redhill extension is going through Building Control, keep the energy information for the doors to hand, as the inspector may ask for it.
If your Redhill builder is about to pour the screed, confirm the finished floor level for the threshold first, because it is very hard to change afterwards.
- 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.
- A check survey once the opening is built means the door is made to the real dimensions, accounting for any small variation in the brickwork or blockwork.
- 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.
Light and sun in Redhill
In Redhill the shortest day has roughly 7 h 52 min of daylight and the longest about 16 h 35 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.
Sliding doors for extensions and garden rooms prices in Redhill
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 Redhill home has been measured.
| Overall width | Typical panels | Guide price (fitted, inc VAT) |
|---|---|---|
| 2.1 m | 2 panels | £5,495–£6,795 |
| 3.0 m | 2 panels | £6,895–£8,395 |
| 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.
From survey to fitted door in Redhill
Surveys in the RH1 district are booked at a time that suits you. Once the opening is ready and measured, manufacture is typically 6–8 weeks for slimline systems after check 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, scheduled to the build programme.
Rules for sliding doors for extensions in England
Doors in an English extension go through the extension's Building Regulations approval. Under Approved Document L, the total area of windows, roof windows and doors is normally capped at 25% of the extension's floor area plus any openings the extension removes, unless your designer shows compensating improvements; the glass must be safety glazing under Approved Document K.
Choosing the specification
- 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 Redhill
Do I need building approval for sliding doors for extensions in Redhill?
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.
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.
When should I order sliding doors for an extension?
Order sliding doors for an extension as soon as the opening is built and a check survey can be done, and agree the target fitting date with your builder in advance. Slimline doors typically take 6–8 weeks to make after sign-off. Getting a quote from drawings early means the specification is settled and only the final measurements are needed.
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.

