Bay and bow windows · England
Triple glazed bay and bow windows in Hertfordshire
Triple glazed bay and bow windows across Hertfordshire: free survey, written fixed quote, and fitting by installation teams working for us. Towns we cover include Watford, Hemel Hempstead and Berkhamsted.

Warmer front rooms on 1930s and Victorian homes. A bay window projects out from the wall in angled sections; a bow window curves in more, shallower sections.
Guide prices across Hertfordshire
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 Hertfordshire
- Watford
- Hemel Hempstead
- Stevenage
- St Albans
- Welwyn Garden City
- Cheshunt
- Hatfield
- Bishop's Stortford
- Borehamwood
- Hitchin
- Hoddesdon
- Letchworth Garden City
- Harpenden
- Bushey
- Hertford
- Rickmansworth
- Potters Bar
- Berkhamsted
Rules in England
The rules for replacement windows in England are set by Approved Document L (2021 edition, with 2023 amendments): 1.4 W/m²K, or a Window Energy Rating of band B or better. Replacement windows are a controlled fitting. A competent person scheme installer (such as FENSA or Certass) self-certifies the work and notifies the council within 30 days; otherwise a building control body approves it.
Planning: Replacing windows on a house is normally permitted development if the new ones look similar. New upper-floor windows in a side wall must be obscure glazed and fixed, or open only above 1.7 m. Flats and maisonettes have no householder permitted development rights, so a change that alters their appearance needs planning permission. An Article 4 direction in a conservation area may mean permission is needed, and listed buildings need listed building consent.
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.
- Guide prices published, not hidden
- No pressure: the quote is yours to keep
- Frames, glass and fitting in one contract
- Advice on planning and consents before you order
Questions
Will the bay be warmer?
Yes. Replacing old double or single glazing in a bay with triple glazing cuts heat loss through the glass and makes the glass surface warmer, so the room feels less draughty.
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 you cover all of Hertfordshire?
We arrange surveys and fitting across Hertfordshire.
Do I need permission for triple glazed bay and bow windows in England?
In England, like-for-like replacements on a house are normally permitted development; flats need permission if the change alters their appearance, Article 4 areas may need permission, and listed buildings need listed building consent.
Bay and bow windows in nearby areas of England
- Buckinghamshire
- Bedfordshire
- Greater London
- Surrey
- Essex
- Berkshire
- Oxfordshire
- Northamptonshire
- Cambridgeshire
- Kent
Other products in Hertfordshire
- 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 Hertfordshire
Written quote fixed for the specification, after a free survey. Building Regulations sign-off by a competent person scheme installer or building control, as the law requires in England.
