Bay and bow windows · Greater London
Triple glazed bay and bow windows in Westminster
We arrange surveys and fitting of triple glazed bay and bow windows in Westminster and the SW1P area, with a written, fixed quote after a free survey.

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.
Winter light and glass choice in Westminster
By midsummer Westminster has about 16 h 38 min of daylight, but in December only around 7 h 50 min, with the noon sun at about 15°. 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 Westminster
| Guide | Supply and fit, inc VAT |
|---|---|
| 3-light bay three windows, about 2.7 m across | £2,995 – £3,795 |
| 5-light bay or bow five windows, about 3.5 m across | £3,795 – £4,695 |
| Two-storey bay ground and first-floor bays | £5,995 – £7,495 |
Guide prices. Your written quote after the free survey fixes the price for the specification shown.
Rules for bay and bow windows in England
England requires replacement windows to achieve 1.4 W/m²K, or a Window Energy Rating of band B or better, which good triple glazing passes comfortably. 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.
Before ordering: 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
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.
- 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 from Westminster
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.
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.
Do I need permission for triple glazed bay and bow windows in Westminster?
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. Check whether your street is in a conservation area or covered by an Article 4 direction before changing the style.
How long does it take to get triple glazed bay and bow windows fitted in Westminster?
After the survey, typical manufacture time is 5 to 8 weeks, and most homes are fitted in 1 to 4 days.
Nearby
We also cover nearby Pimlico (1 km), Chelsea (3 km), Battersea (3 km) and Brixton (4 km).
Other products in Westminster
- 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 in Westminster: book your free survey
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.
