- Postcode district
- HA1
- Survey
- Free for new and replacement doors
- Typical lead time
- Typically 4–6 weeks for the door after the opening is measured; building work scheduled around approvals
- Guide price
- From £6,595 inc VAT
- Nearby
- Pinner, Wembley, Ruislip
- Building rules
- England
Is a sliding door for a new opening a good fit for your home in Harrow?
The right door depends on the opening, the room and the way you use the garden. Here is how sliding doors for new openings tend to work out in practice:
For homes in Harrow that are listed or covered by an Article 4 direction, ask the council about the new opening before paying for structural calculations.
Where a Harrow house has a bay, chimney breast or upstairs window directly above the planned opening, the engineer will need to account for it in the steel design.
- A structural engineer sizes the steel beam and padstones for the actual loads above, so the opening is designed rather than guessed.
- The door is measured from the finished opening rather than from drawings, so it fits the opening as built, not as it was intended to be built.
- If the work affects a party wall, notice can be served under the Party Wall etc. Act 1996 (England and Wales) before it starts, avoiding disputes with neighbours later.
Light and sun in Harrow
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 sliding doors for new openings in Harrow
Guide prices cover the door and forming the opening — steel beam, padstones, making good and structural calculations — fitted, including VAT. Building Control fees are set by your council and are extra.
| Overall width | Typical panels | Guide price (fitted, inc VAT) |
|---|---|---|
| 2.1 m | 2 panels | £7,495–£8,295 |
| 3.6 m | 3 panels | £9,695–£10,895 |
| 4.0 m | 3 panels | £10,295–£11,595 |
See every size on the sliding doors for new openings page or try the guide price tool.
Survey, manufacture and fitting around Harrow
Here is the usual sequence in Harrow: guide price, free survey, written quote, any building work, then manufacture (typically 4–6 weeks for the door after the opening is measured; building work scheduled around approvals). Fitting typically takes 3–5 days of building work, then 1–2 days to fit the door. Nearby, we also survey in Pinner, Wembley and Ruislip.
Do you need approval in Harrow?
A new or wider opening in England needs Building Control approval for the structural work as well as compliance for the door itself under Approved Documents L and K. Expect structural calculations, a steel beam and, where a party wall is involved, notices under the Party Wall etc. Act 1996.
Specification choices for sliding doors for new openings in Harrow
- Widening an existing door. Removing masonry each side of an old patio door to take a wider slider.
- Low threshold detail. Adjusting floor and outside levels during the building work to allow a lower sill.
- Temporary door or boarding. A secure, weathertight closure while the made-to-measure door is being manufactured.
Questions about sliding doors for new openings in Harrow
Can you match other doors and windows in my Harrow home?
Usually, yes. Most aluminium and uPVC systems come in standard RAL colours and finishes, and we can quote dual colour where the inside and outside need to differ. Bring photos of existing frames to the survey.
Do I need planning permission for a new opening?
Planning rules for altering an elevation depend on the property and where you are, so it is worth checking with your council before you commit. Flats, listed buildings and properties covered by an Article 4 direction are the most likely to need consent. Wales and Scotland have their own planning rules. Our planning guide sets out the questions to ask.
Can you turn a window into a sliding door?
Yes, a window opening can usually be extended down to the floor and often widened to take a sliding door. The work involves removing the masonry below the window, forming a new threshold, and fitting a steel beam or lintel if the opening is widened. Drains, air bricks and floor levels outside need checking, and the work needs a Building Regulations application.
Do I need building regulations to widen a door opening?
Yes, forming or widening an opening is structural work and needs a Building Regulations application in England, supported by structural calculations. Building Control inspects the work, typically including the steel and its bearings. In Scotland a building warrant is needed. Wales and Northern Ireland follow their own building regulations through local authority or district council building control.

