- Postcode district
- TS18
- 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
- Billingham, Thornaby-on-Tees, Middlesbrough
- Building rules
- England
Sliding doors for extensions and garden rooms in Stockton-on-Tees: what to know
A few practical points decide whether sliding doors for extensions suit a particular room and opening:
Planning an extension in Stockton-on-Tees? Send us the drawings before the steel is ordered, so the beam above the doors can be designed with the door in mind.
If your Stockton-on-Tees builder is about to pour the screed, confirm the finished floor level for the threshold first, because it is very hard to change afterwards.
- 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.
- We provide the structural opening size and fitting tolerances in writing, giving your builder a clear target and avoiding disputes about who measured what.
- Telling the engineer the door type and span early lets them design the beam above it to limit deflection, protecting the smooth running of large sliding panels.
How much sun will a door in Stockton-on-Tees get?
Daylight in Stockton-on-Tees runs from about 7 h 15 min in December to 17 h 16 min in June, with the noon sun at roughly 12° and 59° respectively. Use that to choose your glass: standard low-E double glazing for north and east elevations, and consider solar-control or triple glazing for sunny south and west walls.
Guide prices for sliding doors for extensions in Stockton-on-Tees
Guide prices are the same across County Durham. They cover the door supplied and fitted into a prepared opening, including VAT, with options itemised in your quote.
| Overall width | Typical panels | Guide price (fitted, inc VAT) |
|---|---|---|
| 2.1 m | 2 panels | £5,495–£6,795 |
| 2.4 m | 2 panels | £5,995–£7,295 |
| 4.0 m | 3 panels | £8,395–£10,195 |
See every size on the sliding doors for extensions page or try the guide price tool.
How fitting works in Stockton-on-Tees
Surveys in the TS18 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.
Specification choices for sliding doors for extensions in Stockton-on-Tees
- Corner opening. Sliding panels meeting at a corner with no post, for extensions open on two sides.
- Solar-control glass. Coated glass for south- and west-facing extensions prone to summer overheating.
- Two-panel slimline. One sliding and one fixed panel, suiting openings up to around 3.6 m depending on the system.
Questions about sliding doors for extensions in Stockton-on-Tees
Do you fit sliding doors for extensions in Stockton-on-Tees?
Yes. We survey and fit sliding doors for extensions in Stockton-on-Tees and across County Durham, including nearby Billingham and Thornaby-on-Tees. Start with a guide price online or call us, and we will arrange a free survey for a new or replacement door.
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.
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.
What structural opening size should my builder leave for sliding doors?
Your builder should leave the structural opening size we give in writing for your chosen door, which is the frame size plus a small fitting tolerance on each side and at the head. The exact figure depends on the system and the threshold detail. We confirm it from your drawings early, then check the built opening before the door is made.

