Bay and bow windows · Northern Ireland
Triple glazed bay and bow windows in County Londonderry
Homes across County Londonderry, including Derry, Coleraine and Magherafelt, can have triple glazed bay and bow windows measured, made to order and fitted.

Coupled triple glazed frames with bay poles where the load needs them. A bay window projects out from the wall in angled sections; a bow window curves in more, shallower sections.
Guide prices across County Londonderry
3-light bay
three windows, about 2.7 m across
£2,995 – £3,795inc VAT · £2,495 – £3,160 ex VAT
- Triple glazed throughout
- Old frames removed and taken away
- Fitted, sealed and made good
5-light bay or bow
five windows, about 3.5 m across
£3,795 – £4,695inc VAT · £3,160 – £3,910 ex VAT
- Triple glazed throughout
- Old frames removed and taken away
- Fitted, sealed and made good
Two-storey bay
ground and first-floor bays
£5,995 – £7,495inc VAT · £4,995 – £6,245 ex VAT
- Triple glazed throughout
- Old frames removed and taken away
- Fitted, sealed and made good
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
Northern Ireland requires replacement windows to achieve 1.6 W/m²K, or a Window Energy Rating of band C or better, which good triple glazing passes comfortably. 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
Can I change a bay to a flat window?
That is a structural and planning change, not a like-for-like replacement. Ask and we will explain what it involves.
How much does a triple glazed bay window cost?
Our guide starts at £2,995 for a three-light uPVC bay, fitted and inc VAT; UK quotes run from about £2,000 to £4,500.
Do bay windows need bay poles?
If the old frames carry load from above, yes. We check on survey and include support in the quote where needed.
Do you cover all of County Londonderry?
We arrange surveys and fitting across County Londonderry.
Do I need permission for triple glazed bay and bow 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.
Bay and bow 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
- Sash 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
Bay and bow 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.
