- Postcode district
- DT11
- Survey
- Free for new and replacement doors
- Typical lead time
- Typically 6–8 weeks for slimline systems after check survey sign-off
- Guide price
- From £5,095 inc VAT
- Nearby
- Wimborne Minster, Ferndown, Wareham
- Building rules
- England
Sliding doors for extensions and garden rooms in Blandford Forum: what to know
A few practical points decide whether sliding doors for extensions suit a particular room and opening:
If your Blandford Forum builder is about to pour the screed, confirm the finished floor level for the threshold first, because it is very hard to change afterwards.
Planning an extension in Blandford Forum? Send us the drawings before the steel is ordered, so the beam above the doors can be designed with the door in mind.
- Agreeing a fitting date with your builder lets the extension be made weathertight on programme, so plastering and flooring can follow without waiting on the doors.
- Being involved at drawing stage means the opening is formed to suit the door, rather than the door being compromised to suit an opening built a few centimetres out.
- Slimline aluminium systems with interlocks typically around 20–25 mm maximise the glass in a new rear wall, keeping the view as open as possible.
How much sun will a door in Blandford Forum get?
Because Blandford Forum sees long summer days (about 16 h 31 min) and short winter ones (about 7 h 56 min), the elevation your door faces makes a real difference. With the midday sun at about 16° in winter, a south-facing door brings light well into the room; a west-facing door catches hot late-afternoon sun in summer.
What should you budget for sliding doors for extensions in Blandford Forum?
The table shows guide prices for common sizes, supplied and fitted, including VAT. Your exact price is fixed in a written quote once the opening in your Blandford Forum home has been measured.
| Overall width | Typical panels | Guide price (fitted, inc VAT) |
|---|---|---|
| 2.4 m | 2 panels | £5,995–£7,295 |
| 4.0 m | 3 panels | £8,395–£10,195 |
| 6.0 m | 4 panels | £11,395–£13,895 |
See every size on the sliding doors for extensions page or try the guide price tool.
From survey to fitted door in Blandford Forum
Surveys in the DT11 district are booked at a time that suits you. Once the opening is ready and measured, manufacture is typically 6–8 weeks for slimline systems after check survey sign-off; on fitting day the frame is set level and sealed, and the panels are adjusted so they glide properly. Fitting usually takes 1–2 days, scheduled to the build programme.
Rules for sliding doors for extensions in England
Doors in an English extension go through the extension's Building Regulations approval. Under Approved Document L, the total area of windows, roof windows and doors is normally capped at 25% of the extension's floor area plus any openings the extension removes, unless your designer shows compensating improvements; the glass must be safety glazing under Approved Document K.
Finishes and extras for sliding doors for extensions
- Three or four panels. More panels for wider extension openings, with one or more sliding.
- Two-panel slimline. One sliding and one fixed panel, suiting openings up to around 3.6 m depending on the system.
- Corner opening. Sliding panels meeting at a corner with no post, for extensions open on two sides.
Questions about sliding doors for extensions in Blandford Forum
How soon can you survey in Blandford Forum?
Surveys in the DT11 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 6–8 weeks for slimline systems after check survey sign-off.
How much do sliding doors for an extension cost?
Slimline sliding doors for an extension have a guide price of £7,795–£9,495 for a 3.6 m opening and £9,595–£11,695 for a 4.8 m opening, fitted, inc VAT at standard 2.1 m height. Taller doors, extra panels, special glass and flush thresholds move the price. Your written quote after the check survey fixes it.
Can you measure from drawings rather than the built opening?
We can quote from drawings, but we manufacture from a check survey of the built opening, because real openings often differ slightly from the plans. Making a large made-to-measure door from drawings alone risks it not fitting. If a programme makes that unavoidable, any arrangement and who carries the risk would be agreed in writing first.
Why does the steel beam matter for sliding doors?
The steel beam above an extension's sliding door matters because every beam bends a little under load, and a large sliding door needs a straight, level head to run freely. If the engineer knows a wide slider will sit under the beam, they can design for low deflection. Too much movement can make panels stiff or bind.