Sash windows · Northern Ireland
Triple glazed sash windows in County Londonderry
Triple glazed sash windows across County Londonderry: free survey, written fixed quote, and fitting by installation teams working for us. Towns we cover include Derry, Coleraine and Magherafelt.
Victorian and Georgian looks with modern glass and locks. A sash window has one or two sashes that slide up and down in a box frame.
Guide prices across County Londonderry
Small window
about 600 x 1000 mm (bathroom, landing)
£1,295 – £1,595inc VAT · £1,080 – £1,330 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)
£1,695 – £2,095inc VAT · £1,410 – £1,745 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)
£2,595 – £3,195inc VAT · £2,160 – £2,660 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 Londonderry
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
We start with a survey, not a sales pitch: measurements, the structure above any bays, trickle-vent needs and escape windows. The quote that follows fixes the price, and anything unexpected on the day is agreed with you first.
- 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
Will triple glazing make my sashes heavy to lift?
The balances are sized for the sash weight, so they should slide smoothly. Heavier sashes use stronger balances or weights.
Can I keep my original sash boxes?
Sometimes. A timber specialist can fit new sashes into sound original boxes, but the glass thickness is limited by the sash depth.
How much do triple glazed sash windows cost?
Our guide starts at £1,295 for a small uPVC sash, fitted and inc VAT. Timber sashes cost more; UK quotes for timber triple sashes run past £3,000 each.
Do you cover all of County Londonderry?
We arrange surveys and fitting across County Londonderry.
Do I need permission for triple glazed sash 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.
Sash windows in nearby areas of Northern Ireland
Other products in County Londonderry
- uPVC windows
- Aluminium windows
- Timber windows
- Alu-clad timber windows
- Casement windows
- Flush casement windows
- Tilt and turn 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
Sash windows across County Londonderry
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.