- Postcode district
- TN16
- Survey
- Free for new and replacement doors
- Typical lead time
- Typically 4–6 weeks for aluminium and 2–4 weeks for uPVC after survey sign-off
- Guide price
- From £3,295 inc VAT
- Nearby
- Oxted, Sevenoaks, Orpington
- Building rules
- England
What replacement sliding doors offer homes in Westerham
Here is what to weigh up if you are considering replacement sliding doors for a home in Westerham:
If your Westerham home still has its original sliding patio door, look at the glass beads: if they are on the outside, a replacement will close off that weakness.
Considering a wider door for your Westerham home while you are replacing it? Weigh up the extra cost of structural work against the gain in glass before deciding.
- New rollers and a precision track make a heavy door glide with a light push, where an old door may need both hands and a firm shove to open.
- Certification through a competent person scheme installer, or notification to Building Control, is arranged as part of the job and gives you a record for when you sell.
- Most two-panel replacements are completed in a single day, so the house is secure again by the evening without the room being out of use for long.
Daylight in Westerham and what it means for your glass
Sun angles matter for big glazed doors. Around Westerham, midday sun reaches about 62° in summer and drops to about 15° in winter. That low winter sun is free heat through south-facing glass; high summer sun is easier to shade with a roof overhang, and solar-control glass helps where there is none.
How much do replacement sliding doors cost in Westerham?
Use these guide prices to budget. They include VAT, fitting and taking away an old door of a similar size. Taller doors, triple glazing and dual colour add to the figure — the online tool shows how much.
| Overall width | Typical panels | Guide price (fitted, inc VAT) |
|---|---|---|
| 2.1 m | 2 panels | £3,995–£4,895 |
| 3.6 m | 3 panels | £5,595–£6,895 |
| 4.8 m | 4 panels | £6,995–£8,495 |
See every size on the replacement sliding doors page or try the guide price tool.
From survey to fitted door in Westerham
Surveys in the TN16 district are booked at a time that suits you. After you approve the quote, manufacture is typically 4–6 weeks for aluminium and 2–4 weeks for uPVC after survey sign-off; on fitting day the old door comes out, the new frame is set level and sealed, and the panels are adjusted so they glide properly. Fitting usually takes 1 day for a straight two-panel swap; 1–2 days for larger doors.
Rules for replacement sliding doors in England
In England, a replacement sliding door is a controlled fitting under the Building Regulations. In an existing home, a door with more than 60% glazing must reach a U-value of 1.4 W/m²K or better (or a Doorset Energy Rating of band C) under Approved Document L, and glass in doors must be safety glazing under Approved Document K. We arrange compliance through a competent person scheme installer or by notifying Building Control, and you receive the certificate.
Choosing the specification
- Aluminium replacement. A thermally broken aluminium slider with slim frames and a durable powder-coat finish.
- Upgraded glass. Triple, laminated, solar-control or obscure glass to suit the elevation.
- New internal cill or board. A fresh window board or reveal lining to finish the inside neatly.
Questions about replacement sliding doors in Westerham
Do I need building approval for replacement sliding doors in Westerham?
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 I get a bigger door in the same opening?
You can usually get more glass in the same opening, because modern frames are slimmer, but the overall door size stays roughly the same as the old one. Making the door wider or taller means widening the opening, which is structural work with a steel beam, calculations and a Building Regulations application. Our new openings page covers that.
Is the survey free for a replacement door?
Yes, the survey for a replacement sliding door is free. We measure the opening, check its condition and the support above it, look at floor and outside levels, and talk through frame, glass and colour options. You then receive a written quote with the fixed price, and nothing is ordered until you confirm the surveyed specification in writing.
Do I need planning permission to replace a sliding door?
Replacing doors on a house is usually permitted development, so no planning application is needed, as long as the new doors are similar in appearance to the existing ones. Flats, listed buildings and properties covered by an Article 4 direction may need consent. Our planning guide explains more.

