Sliding patio doors · Northern Ireland
Triple glazed sliding patio doors in County Down
From Bangor to Downpatrick, we arrange triple glazed sliding patio doors for homes across County Down, with every quote fixed for the specification shown.

Large sliding panels in triple glass on rollers rated for the weight. A sliding patio door has large glazed panels that slide past each other on a track, so it opens without swinging into the room.
Guide prices across County Down
uPVC 2-pane slider
about 1.8 m wide
£1,895 – £2,295inc VAT · £1,580 – £1,910 ex VAT
- Triple glazed panels
- Removal of the old door or window
- Fitted, sealed and finished
uPVC 2-pane slider, wide
about 2.4 m wide
£2,295 – £2,895inc VAT · £1,910 – £2,410 ex VAT
- Triple glazed panels
- Removal of the old door or window
- Fitted, sealed and finished
Aluminium slider
about 3 m wide
£3,295 – £4,195inc VAT · £2,745 – £3,495 ex VAT
- Triple glazed panels
- Removal of the old door or window
- Fitted, sealed and finished
Guide prices, supply and fit. The written quote after your survey fixes the price for the specification shown; anything extra is agreed with you first.
Towns in County Down
Rules in Northern Ireland
In Northern Ireland, replacement external doors must meet 1.8 W/m²K. Replacing external doors does not need full plans or a building notice, but the work must still comply; enlarging an opening or other structural change needs building control approval.
Planning: Check with your council planning office before changing the style, material or size of doors, and always for listed buildings, conservation areas and flats.
How it works
The surveyor measures every opening, checks ventilation, escape windows and safety-glass zones, and talks through styles. Your written quote lists each item with its glass build-up and U-value, and the price is fixed for that specification.
- Every opening measured, including escape and vent needs
- Frames rated for the weight of triple glass
- Old windows removed and taken away
- Each opening closed up the same day
Questions
Do sliding doors need safety glass?
Yes, all door glass must be safety glass. Triple units in sliders are toughened or laminated.
Can I have a level threshold?
Low thresholds are available; they need a suitable drainage detail outside, which we check on survey.
How much does a triple glazed sliding door cost?
Our guide starts at £1,895 fitted for a 1.8 m uPVC slider and £3,295 for a 3 m aluminium slider, inc VAT. UK quotes for triple uPVC sliders run from about £1,600 to £2,600.
Do you cover all of County Down?
We arrange surveys and fitting across County Down.
Do I need permission for triple glazed sliding patio doors in Northern Ireland?
In Northern Ireland, check with your council planning office before changing the style, material or size of a door, and always for listed buildings and flats.
Sliding patio doors in nearby areas of Northern Ireland
Other products in County Down
- uPVC windows
- Aluminium windows
- Timber windows
- Alu-clad timber windows
- Casement windows
- Flush casement windows
- Tilt and turn windows
- Sash windows
- Bay and bow windows
- Fixed and picture windows
- Composite front doors
- French doors
- Bifold doors
- Glass-only replacement
- Acoustic triple glazing
- Security glazing
- Whole-house replacement
- New builds and self-builds
- Period homes and conservation areas
- Flats and apartments
- Passivhaus and EnerPHit
Sliding patio doors across County Down
Written quote fixed for the specification, after a free survey. No building notice is needed for a straight replacement in Northern Ireland; we fit to the regulations and give you a written handover pack.
