- Postcode district
- RH6
- 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
- Crawley, Redhill, Reigate
- Building rules
- England
What sliding doors for extensions offer homes in Horley
Most homeowners choosing sliding doors for extensions want the same things: more light, a clear view and a door that is easy to live with.
Self-building in Horley or elsewhere in Surrey? Ask for the sliding doors to be quoted as part of a wider glazing package so the frames, colours and glass match across the house.
When your Horley extension is going through Building Control, keep the energy information for the doors to hand, as the inspector may ask for it.
- 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.
- 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.
- 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.
How much sun will a door in Horley get?
At the latitude of Horley, the midday sun climbs to about 62° in late June but only about 15° in late December, when daylight lasts around 7 h 53 min against 16 h 35 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.
Guide prices for sliding doors for extensions in Horley
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 Horley home has been measured.
| Overall width | Typical panels | Guide price (fitted, inc VAT) |
|---|---|---|
| 3.6 m | 2 panels | £7,795–£9,495 |
| 4.0 m | 3 panels | £8,395–£10,195 |
| 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.
How fitting works in Horley
Here is the usual sequence in Horley: 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 Crawley, Redhill and Reigate.
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.
Options to consider for your sliding door for an extension
- Flush threshold. A level floor from inside to out, with a drainage channel set into the patio.
- Solar-control glass. Coated glass for south- and west-facing extensions prone to summer overheating.
- 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 Horley
Is the price different in Horley?
No. Guide prices for sliding doors for extensions are the same across mainland Britain, including Horley. The fitted price depends on size, system, glass and finish, and any structural work, all fixed in your written quote after survey.
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.
Can you work with my builder and architect?
Yes, working with your builder, architect and structural engineer is the normal way we approach extension doors. We can provide technical details, opening sizes, threshold requirements and fixing information, and attend site for the check survey. Your builder forms the opening and prepares the floor, and our installers fit the doors to the agreed programme.
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.

