New and widened openings for sliding doors across Cornwall
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:
Turning a Cornwall kitchen window into a door to the garden? Check where drains, gullies and air bricks sit outside, because they can affect the new threshold.
For homes in Cornwall that are listed or covered by an Article 4 direction, ask the council about the new opening before paying for structural calculations.
- Structural calculations are included in the guide price, and the Building Regulations application is handled as part of the project, so you are not left coordinating engineers and inspectors.
- Widening a standard patio opening to a larger span can transform how a room connects to the garden, giving a wall of glass rather than a doorway.
- Making good the reveals and head after the steel goes in leaves a square, plumb opening, which is what a precision-made sliding door needs to run smoothly.
Guide prices for sliding doors for new openings in Cornwall
Use these guide prices to budget for the whole job in Cornwall: the door, the steelwork, making good and the engineer's calculations, including VAT. Building Control or warrant fees are charged by the council on top.
| Overall width | Typical panels | Guide price (fitted, inc VAT) |
|---|---|---|
| 1.8 m | 2 panels | £6,995–£7,795 |
| 2.1 m | 2 panels | £7,495–£8,295 |
| 3.6 m | 3 panels | £9,695–£10,895 |
| 6.0 m | 4 panels | £13,295–£15,095 |
Every size is on the sliding doors for new openings page.
Daylight and glass in Cornwall
In Cornwall the shortest day has roughly 8 h 01 min of daylight and the longest about 16 h 26 min. The noon sun sits near 16° above the horizon in winter and 63° in summer — so glass that faces south collects useful warmth from October to March, while a west-facing door may need solar control to stop it overheating in July.
Towns we cover in Cornwall
We survey and fit sliding doors for new openings in 15 towns across Cornwall, including the EX23, PL12, PL14, PL15, PL25, PL27 postcode districts.
Approvals in England
In England, forming or widening an opening is structural work that needs a Building Regulations application, structural calculations and usually a steel beam on padstones. The new door is also a controlled fitting (U-value 1.4 W/m²K or better if more than 60% glazed). If steelwork bears on a party wall, the Party Wall etc. Act 1996 may apply.
Questions about sliding doors for new openings in Cornwall
Is the price different in Cornwall?
No. Guide prices for sliding doors for new openings are the same across mainland Britain, including Cornwall. The fitted price depends on size, system, glass and finish, and any structural work, all fixed in your written quote after survey.
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.
How much does it cost to widen an opening for sliding doors?
Our guide price for forming or widening an opening is £3,595 for 2.4 m and £4,495 for 4.8 m, covering steel, padstones, making good and structural calculations. The door is priced separately, and Building Control fees are set by your council. All figures are guide prices inc VAT, fixed in a written quote after we survey the wall and see what is above it.
How long does it take to form a new opening?
Forming or widening an opening typically involves 3–5 days of building work, including propping, cutting out, installing the steel and padstones, and making good. The sliding door is then made to the finished opening, which typically takes 4–6 weeks for aluminium, so a secure temporary closure is fitted in between. The door itself typically goes in within one to two days.