Are sliding doors for extensions right for homes in County Down?
Most homeowners choosing sliding doors for extensions want the same things: more light, a clear view and a door that is easy to live with.
Where an extension in County Down faces south or west, ask about solar-control glass, because a wall of glass in a single-storey room can overheat in summer.
When your County Down extension is going through Building Control, keep the energy information for the doors to hand, as the inspector may ask for it.
- 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.
- A check survey once the opening is built means the door is made to the real dimensions, accounting for any small variation in the brickwork or blockwork.
- 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.
Guide prices for sliding doors for extensions in County Down
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 |
| 2.1 m | 2 panels | £5,495–£6,795 |
| 2.4 m | 2 panels | £5,995–£7,295 |
| 4.8 m | 3 panels | £9,595–£11,695 |
Every size is on the sliding doors for extensions page.
Daylight and glass in County Down
Daylight in County Down runs from about 7 h 17 min in December to 17 h 14 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.
Towns we cover in County Down
We survey and fit sliding doors for extensions in 13 towns across County Down, including the BT18, BT20, BT21, BT23, BT24, BT25 postcode districts.
Approvals in Northern Ireland
Extensions in Northern Ireland are approved by district council building control under the Building Regulations (Northern Ireland), including their doors. We take on work in Northern Ireland by arrangement.
Questions about sliding doors for extensions in County Down
Do I need building approval for sliding doors for extensions in County Down?
In Northern Ireland the Building Regulations (Northern Ireland) apply through district council building control; work there is by arrangement. We confirm the right route for your property at survey, so the paperwork is in place before fitting.
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.
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 sliding doors suit a garden room?
A garden room usually suits a two-panel or three-panel sliding door sized to the front of the building, with a header strong enough to carry the roof without pressing on the frame. Aluminium systems are a common choice because they are stable and need little maintenance. Glass with good insulation helps if the room will be used all year.