New builds and self-builds · County Down
Triple glazing for new builds and self-builds in Castlereagh
From the first measure to the handover pack, we handle new-build triple glazing for homes in Castlereagh and the rest of County Down.

Window and door packages priced from drawings and fitted to your programme. Triple glazing is not required by Building Regulations for new homes, but it helps a new dwelling meet its overall energy target.
Winter light and glass choice in Castlereagh
In Castlereagh, midday sun in late December sits around 12° high, with roughly 7 h 15 min of daylight. For windows facing north or shaded by neighbours, cutting heat loss matters more than solar gain; on open south-facing glass, ask about a higher solar-gain unit.
Guide prices in Castlereagh
| Guide | Supply and fit, zero-rated (new home) |
|---|---|
| uPVC package about 22 m2 of windows and doors | £11,195 – £13,895 |
| Aluminium package about 22 m2 of windows and doors | £18,895 – £23,595 |
| Alu-clad timber package about 22 m2 of windows and doors | £24,795 – £30,995 |
Guide prices. Your written quote after the free survey fixes the price for the specification shown.
Rules for new builds and self-builds in Northern Ireland
For a new home in Northern Ireland, windows and doors are approved through the build’s full plans application to council Building Control: they must average 1.40 W/m²K, with no single unit worse than 3.00. The house itself needs planning permission.
VAT: supply and fitting by a VAT-registered contractor in the construction of a new home is normally zero-rated, so new-build guide prices are shown without VAT; supply-only purchases carry 20% VAT, which self-builders can usually reclaim through HMRC’s DIY housebuilders scheme.
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
Is triple glazing mandatory for new builds?
No. Neither the current rules nor the Future Homes Standard make it compulsory. Triple glazing helps meet the overall energy target.
How much does a self-build window package cost?
For about 22 m² of windows and doors, our guide starts at £11,195 in uPVC and £18,895 in aluminium, fitted and zero-rated (new home).
Do you fit new-build triple glazing 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.
Do I need permission for new-build triple glazing in Castlereagh?
In Northern Ireland, a new home needs planning permission, and its windows and doors are approved through the build’s own Building Regulations application rather than as replacements.
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
- Glass-only replacement
- Acoustic triple glazing
- Security glazing
- Whole-house replacement
- Period homes and conservation areas
- Flats and apartments
- Passivhaus and EnerPHit
New builds and self-builds 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.
