What are replacement sliding doors?
Sliding door replacement means taking out an existing patio door and fitting a new, made-to-measure sliding door into the same opening, without widening it or changing the structure. It is the simplest way to deal with a door that sticks, leaks, lets in draughts, has misted glass or feels insecure. The new door is built to the measurements we take at a free survey, and removal and disposal of the old door are included in our guide prices.
Most replacements are a one-day job for a two-panel door. We protect the floor, remove the old frame, check the opening and the support above it, fit and level the new frame, then seal it inside and out and finish with trims. A modern thermally broken aluminium or uPVC door usually gives more glass, smoother running, better seals and multipoint locking compared with the door it replaces, and a lower threshold may be possible depending on your floor and outside levels.
In England a replacement door is a controlled fitting under the Building Regulations, so the work must meet the energy and safety glazing rules and be certified through a competent person scheme installer or notified to Building Control. We arrange that as part of the job. Replacing a door on a house is usually permitted development if the new one looks similar, but flats, listed buildings and Article 4 areas may need consent.
Who are they for?
Best suited to
- Draughty or leaking old patio doors
- Doors that stick, jump the track or will not lock
- Misted or single glazed panels
- Upgrading security on a rear door
Worth considering
- Keeping the same opening limits the new door to roughly the old size; a wider door means structural work.
- Removing an old frame can disturb plaster and render around the reveals, which may need making good and redecorating.
- A lower threshold is not always possible if the floor inside sits close to the outside ground or patio level.
Why choose replacement sliding doors?
- Removal and disposal of your old patio door is included in our guide prices, so there is no separate skip or tip run to organise.
- Because the opening stays the same size, a straight replacement avoids structural work, steel beams and a Building Regulations structural application.
- Slimmer modern frames often give a larger area of glass within the same opening, letting more daylight into the room than the old door did.
- A thermally broken frame with modern double glazing must achieve 1.4 W/m²K or better in England for a door in an existing home with more than 60% glazing, which is far better than most old sliders.
- Multipoint locks, anti-lift devices and internally beaded glass close the security gaps that older patio doors commonly have, such as panels that can be lifted out.
- 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.
Typical specification
| Scope | Remove old door, fit new door in the same opening, seal and trim |
|---|---|
| Removal | Old door removed and disposed of, included in guide prices |
| Survey | Free survey to measure and check the opening |
| Typical fitting time | 1 day for a straight swap of a 2-panel door; 1–2 days for larger doors |
| Compliance (England) | Competent person scheme certification or Building Control notification |
| Energy (England) | 1.4 W/m²K or better for doors in existing homes with more than 60% glazing |
| Making good | Internal reveals and trims; scope confirmed in your quote |
Figures are typical and vary by system and size; your quote confirms the exact specification.
How much do replacement sliding doors cost?
Replacing a 2.4 m two-panel patio door with a new aluminium slider has a guide price of £4,295–£5,295, fitted, inc VAT at standard 2.1 m height, including removal and disposal of the old door, with the final price fixed in a written quote after a free survey.
| Overall width | Typical panels | Guide price (fitted, inc VAT) |
|---|---|---|
| 1.5 m | 2 panels | £3,295–£4,095 |
| 1.8 m | 2 panels | £3,695–£4,495 |
| 2.1 m | 2 panels | £3,995–£4,895 |
| 2.4 m | 2 panels | £4,295–£5,295 |
| 3.0 m | 2 panels | £4,995–£6,095 |
| 3.6 m | 3 panels | £5,595–£6,895 |
| 4.0 m | 3 panels | £6,095–£7,395 |
| 4.8 m | 4 panels | £6,995–£8,495 |
| 6.0 m | 4 panels | £8,295–£10,095 |
Guide prices for a standard 2.1 m high door, supplied and fitted, including VAT and removal of an old door of similar size. Your price is fixed in a written quote after survey.
Options and extras
- Aluminium replacement. A thermally broken aluminium slider with slim frames and a durable powder-coat finish.
- uPVC replacement. A cost-conscious choice for a straightforward swap, available in white and foiled colours.
- Slimline upgrade. Narrow interlocks for the maximum glass area the existing opening allows.
- Lower threshold. A reduced-height sill where floor and outside levels allow, with suitable drainage.
- 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.
Lead times and fitting
Lead time: Typically 4–6 weeks for aluminium and 2–4 weeks for uPVC after survey sign-off.
Fitting: Typically 1 day for a straight two-panel swap; 1–2 days for larger doors.
Nothing is ordered until you confirm the surveyed specification in writing. See how it works.
Rules and approvals
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.
Wales
In Wales, replacement doors are covered by the Building Regulations as applied in Wales, including the Welsh Part L energy requirements and safety glazing rules. Compliance is arranged through a competent person scheme installer or your council's Building Control, and the certificate is kept with your property records.
Scotland
In Scotland, replacing a door like for like in a house does not usually need a building warrant, but the new door must still meet the Scottish building standards for energy and safety. Forming or widening an opening is different: that needs a building warrant from the council before work starts.
Northern Ireland
In Northern Ireland, the Building Regulations (Northern Ireland) apply through your district council's building control service, with energy guidance in Technical Booklet F1. Work in Northern Ireland is by arrangement, and we confirm the approval route for your property at survey.
Replacement sliding doors: common questions
How long does it take to replace a sliding patio door?
Replacing a two-panel sliding patio door typically takes one day, from removing the old door to sealing and trimming the new one. Larger doors, three- or four-panel sets and doors needing extra making good typically take one to two days. Manufacture comes first, typically 4–6 weeks for aluminium or 2–4 weeks for uPVC after you sign off the surveyed specification.
Do I need building regulations approval to replace a patio door?
In England a replacement door is a controlled fitting, so it must meet the Building Regulations for energy and safety glazing. You do not apply in advance; instead the work is self-certified by a competent person scheme installer or notified to Building Control, which we arrange. In Scotland like-for-like replacement in a house usually needs no building warrant but must still meet the building standards.
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.
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.
What happens to my old patio door?
We remove your old patio door and take it away for disposal as part of the job, and that is included in our guide prices, so there is nothing for you to arrange. If you would rather keep the old door, for example for a shed or greenhouse project, tell us before the fitting day and we will leave it safely on site.
Will the new door have a lower threshold?
A lower threshold may be possible on a replacement, depending on the floor level inside, the height of the patio or ground outside and how the opening was built. Low thresholds are typically 15–25 mm. A flush threshold needs a drainage channel outside so rain cannot run in. We check levels at survey and tell you what is realistic.
What if there is no proper lintel above my old door?
Occasionally an old door frame turns out to be carrying some load because the support above the opening is inadequate or missing. We check the head of the opening at survey and again when the old frame comes out. If extra support is needed, we explain why, what it involves and what it costs before any further work goes ahead.
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.