Flush casement windows · Northern Ireland
Triple glazed flush casement windows in County Antrim
We survey and fit triple glazed flush casement windows across County Antrim, from Belfast and Lisburn to smaller towns such as Ballymoney.

A softer, flatter face for cottages and older homes. A flush casement window has sashes that close flush with the outer frame instead of overlapping it, copying the look of traditional timber windows.
Guide prices across County Antrim
Small window
about 600 x 1000 mm (bathroom, landing)
£845 – £1,095inc VAT · £705 – £910 ex VAT
- uPVC frame, triple glazed, warm-edge spacers
- Removal and disposal of the old window
- Fitted, sealed and made good inside and out
Medium window
about 1200 x 1200 mm (bedroom)
£1,195 – £1,495inc VAT · £995 – £1,245 ex VAT
- uPVC frame, triple glazed, warm-edge spacers
- Removal and disposal of the old window
- Fitted, sealed and made good inside and out
Large window
about 1800 x 1200 mm (lounge)
£1,795 – £2,195inc VAT · £1,495 – £1,830 ex VAT
- uPVC frame, triple glazed, warm-edge spacers
- Removal and disposal of the old window
- Fitted, sealed and made good inside and out
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 Antrim
Rules 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.
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
After the free survey you get a written quote naming the frame system, the glass build-up and the whole-window U-value for every item. Windows are made to order, then fitted, sealed and made good, one opening at a time.
- 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
Can flush casements be triple glazed?
Yes. The frame depth and hardware are chosen for the unit weight; we confirm the exact unit on your quote.
What colours are available?
Woodgrain foils and heritage colours in uPVC, and any paint colour in timber or RAL colour in aluminium.
Will they be accepted in a conservation area?
Flush designs are often the closest match to original timber windows, but each council decides. See our conservation guide and check any Article 4 direction.
Do you cover all of County Antrim?
We arrange surveys and fitting across County Antrim.
Do I need permission for triple glazed flush casement windows in Northern Ireland?
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.
Flush casement windows in nearby areas of Northern Ireland
Other products in County Antrim
- uPVC windows
- Aluminium windows
- Timber windows
- Alu-clad timber windows
- 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
- New builds and self-builds
- Period homes and conservation areas
- Flats and apartments
- Passivhaus and EnerPHit
Flush casement windows across County Antrim
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.
