Are sliding doors for extensions right for homes in County Durham?
The right door depends on the opening, the room and the way you use the garden. Here is how sliding doors for extensions tend to work out in practice:
Where an extension in County Durham faces south or west, ask about solar-control glass, because a wall of glass in a single-storey room can overheat in summer.
For a garden room at the bottom of a County Durham garden, think about access: large glass panels need a clear route from the road to the site.
- 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.
- 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.
- 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.
Guide prices for sliding doors for extensions in County Durham
These are guide prices for fitted doors, including VAT. They run from an entry-level system to a premium one at the same size; the survey confirms which suits your opening.
| Overall width | Typical panels | Guide price (fitted, inc VAT) |
|---|---|---|
| 1.8 m | 2 panels | £5,095–£6,195 |
| 2.4 m | 2 panels | £5,995–£7,295 |
| 3.6 m | 2 panels | £7,795–£9,495 |
| 4.8 m | 3 panels | £9,595–£11,695 |
Every size is on the sliding doors for extensions page.
Daylight and glass in County Durham
At the latitude of County Durham, the midday sun climbs to about 59° in late June but only about 12° in late December, when daylight lasts around 7 h 14 min against 17 h 18 min in midsummer. A south-facing sliding door for an extension lets that low winter sun deep into the room; on a west or south elevation, solar-control glass keeps summer afternoons comfortable.
Towns we cover in County Durham
We survey and fit sliding doors for extensions in 14 towns across County Durham, including the DH1, DH3, DH8, DH9, DL1, DL12 postcode districts.
Approvals in England
In England, sliding doors in a new extension are covered by the extension's own Building Regulations application rather than a separate door notification. Approved Document L limits the glazed area: windows, roof windows and doors should not normally exceed 25% of the extension's floor area plus the area of any windows or doors lost to the extension, unless the extra glass is compensated for elsewhere. The doors must also meet the energy and safety glazing standards.
Questions about sliding doors for extensions in County Durham
Do you fit sliding doors for extensions in County Durham?
Yes. We survey and fit sliding doors for extensions in County Durham and across County Durham, including Darlington and Hartlepool. Start with a guide price online or call us, and we will arrange a free survey for a new or replacement door.
When should I order sliding doors for an extension?
Order sliding doors for an extension as soon as the opening is built and a check survey can be done, and agree the target fitting date with your builder in advance. Slimline doors typically take 6–8 weeks to make after sign-off. Getting a quote from drawings early means the specification is settled and only the final measurements are needed.
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.
How do I get a level threshold in an extension?
A level or flush threshold in an extension needs the finished floor level inside to be set relative to the door sill and the outside paving before the screed goes down. Outside, a drainage channel is needed across the threshold so rain cannot run in. Our thresholds guide explains the options.

