- Postcode district
- HA1
- 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
- Pinner, Wembley, Ruislip
- Building rules
- England
Why choose replacement sliding doors in Harrow?
The right door depends on the opening, the room and the way you use the garden. Here is how replacement sliding doors tend to work out in practice:
Considering a wider door for your Harrow home while you are replacing it? Weigh up the extra cost of structural work against the gain in glass before deciding.
If the existing opening in your Harrow home is sound and a sensible size, simply replacing the door gives the biggest improvement for the least disruption.
- 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.
- 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.
- Because the opening stays the same size, a straight replacement avoids structural work, steel beams and a Building Regulations structural application.
Daylight in Harrow and what it means for your glass
Because Harrow sees long summer days (about 16 h 39 min) and short winter ones (about 7 h 49 min), the elevation your door faces makes a real difference. With the midday sun at about 15° in winter, a south-facing door brings light well into the room; a west-facing door catches hot late-afternoon sun in summer.
Guide prices for replacement sliding doors in Harrow
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.
What happens when you order replacement sliding doors in Harrow?
Surveys in the HA1 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.
Do you need approval in Harrow?
English Building Regulations treat a new or replacement external door in an existing home as a controlled fitting: it needs a U-value of 1.4 W/m²K or better (or Doorset Energy Rating band C) if more than 60% of it is glazed (Approved Document L), and safety glass in a critical location (Approved Document K). Compliance is arranged through a competent person scheme installer or a Building Control notification, so you get a certificate for your records.
Choosing the specification
- 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.
- Slimline upgrade. Narrow interlocks for the maximum glass area the existing opening allows.
Questions about replacement sliding doors in Harrow
How soon can you survey in Harrow?
Surveys in the HA1 district are booked at a time that suits you, and we offer survey dates when we reply to your enquiry. After you approve the written quote, manufacture is typically 4–6 weeks for aluminium and 2–4 weeks for uPVC after survey sign-off.
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.
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.
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.