Glass-only replacement · County Down
Triple glazed sealed unit replacement in Castlereagh
Triple glazed replacement sealed units for homes in Castlereagh: measured on a free survey, made to order and fitted by installation teams working for us across County Down.
Triple units for frames that can take them; better double units when they cannot. Sealed unit replacement means changing only the glass in an existing frame.
Winter light and glass choice in Castlereagh
On the shortest day, Castlereagh gets about 7 h 15 min of daylight and the midday sun reaches only about 12° above the horizon. Low winter sun means north-facing rooms here gain little solar heat, which is where triple glazing’s lower heat loss helps most.
Guide prices in Castlereagh
| Guide | Supply and fit, inc VAT |
|---|---|
| Small unit up to about 0.6 m2, frame checked first | £145 – £195 |
| Medium unit about 0.6 to 1.2 m2 | £195 – £245 |
| Large unit about 1.2 to 2 m2 | £295 – £395 |
Guide prices. Your written quote after the free survey fixes the price for the specification shown.
Rules for glass-only replacement in Northern Ireland
In Northern Ireland, replacement windows must meet 1.6 W/m²K, or a Window Energy Rating of band C or better. Replacing windows or 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 windows or 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.
- Free survey and a written quote fixed for the specification
- Glass build-up and whole-window U-value on every quote
- Written handover pack at the end of the job
- Guarantees on frames, units and fitting in writing
Questions from Castlereagh
Why are my windows misting between the panes?
The seal around the unit has failed and moist air has got in. Only replacing the unit fixes it.
Will heavier glass damage my hinges?
It can. Triple units are about 50% heavier, so hinges and packers are checked and upgraded where needed.
Do I need permission for triple glazed replacement sealed units in Castlereagh?
In Northern Ireland, check with your council planning office before changing the style, material or size of windows, and always for listed buildings and flats. Check whether your street is in a conservation area or covered by an Article 4 direction before changing the style.
Do you fit triple glazed replacement sealed units in Castlereagh?
Yes. We arrange surveys and fitting in Castlereagh and across County Down. Send your postcode and the windows or doors you want replaced, and we will book a free survey.
Nearby
Also near Castlereagh: Belfast (4 km), Holywood (8 km), Newtownabbey (10 km) and Lisburn (11 km).
Other products in Castlereagh
- 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
- Sliding patio doors
- Bifold doors
- Acoustic triple glazing
- Security glazing
- Whole-house replacement
- New builds and self-builds
- Period homes and conservation areas
- Flats and apartments
- Passivhaus and EnerPHit
Glass-only replacement in Castlereagh: book your free survey
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.