Whole-house replacement · County Down
Whole-house triple glazing in Castlereagh
We arrange surveys and fitting of whole-house triple glazing in Castlereagh and the BT5 area, with a written, fixed quote after a free survey.

One survey, one fitting team, one matched look. Whole-house triple glazing means replacing every window, and usually the external doors, in one job.
Winter light and glass choice in Castlereagh
By midsummer Castlereagh has about 17 h 16 min of daylight, but in December only around 7 h 15 min, with the noon sun at about 12°. Triple glazing keeps more heat in during those long, dark months; big south and west windows may suit solar-control glass for summer.
Guide prices in Castlereagh
| Guide | Supply and fit, inc VAT |
|---|---|
| 2-bed terrace 5 windows + front door | £5,695 – £7,195 |
| 3-bed semi 9 windows + front door | £9,395 – £11,795 |
| 4-bed detached 12 windows + front door + French doors | £13,595 – £16,995 |
Guide prices. Your written quote after the free survey fixes the price for the specification shown.
Rules for whole-house replacement in Northern Ireland
The rules for replacement windows in Northern Ireland are set by Technical Booklet F1 (2022): 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.
Before ordering: 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.
- 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 from Castlereagh
How much does it cost to triple glaze a 3-bed semi?
Our guide is £9,395 to £11,795 for 9 uPVC windows and a front door, fitted and inc VAT. UK quotes typically range from about £6,500 to £11,000 for windows only.
How long does a whole-house installation take?
Usually 1 to 2 days for a small house and 2 to 4 days for a larger one.
How long does it take to get whole-house triple glazing fitted in Castlereagh?
After the survey, typical manufacture time is 4 to 8 weeks, and most homes are fitted in 1 to 4 days.
Do you fit whole-house 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.
Nearby
Nearby towns on our list include 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
- New builds and self-builds
- Period homes and conservation areas
- Flats and apartments
- Passivhaus and EnerPHit
Whole-house 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.
