Fenster Glazing
Bow and Bay Windows
Bow and bay windows add light, shape and usable depth to the front of a home. We help plan the window style, angles, support, colour and glazing so the feature improves the room rather than simply replacing like-for-like frames.
Window configuration
Frames joined at an angle, standing proud of the wall.
A bay is a run of frames joined by angled posts, so the run steps out past the face of the wall. A bow does the same across more facets at shallower angles, which reads as a curve. What projects is the window you already chose, built as three, four or five lights rather than one, and the room gains the depth it projects.
The shape is the arrangement of the frames. The window inside it is specified exactly as it would be on a flat elevation.
Where you can have it
Any of our windows can form a bay.
The lights in a bay are ordinary windows joined together. Fixed panes, openers, or a mixture across the run.
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uPVC
uPVC Casement Windows
The usual replacement for an existing uPVC or timber bay.
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uPVC
uPVC Flush Sash Windows
Flush sashes across the run, for a period elevation.
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uPVC
Sliding Sash Windows
Vertical sliders in a bay, as most Victorian bays were originally built.
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uPVC
uPVC Tilt & Turn Windows
Inward opening lights, cleaned from inside the room.
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Aluminium
Aluminium Casement Windows
Slim Prestige sightlines, so the angled posts take less of the glass.
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Aluminium
Aluminium Flush Windows
The flush aluminium outer frame across the run.
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Aluminium
Aluminium Heritage Windows
Steel-look sections for a bay on a period frontage.
What holds it up
A bay carries the wall above it.
A bay stands proud of the wall, which means the wall above it is sitting on the bay rather than on the brickwork behind. On most houses that load is already carried by the existing frames, and replacing them is the moment it has to be handled properly rather than assumed.
This is a survey question rather than a catalogue one, and it is the reason a bay is measured and specified before anything is priced as fitted. Where support is needed it is specified as part of the job.
What we check before it is ordered
- What is above
- Roof, brickwork or a second bay
- How it is carried
- Existing loading, and what replaces it
- The angle
- Set angles for a bay, shallower facets for a bow
Specification
What gets decided on a bay.
- Shape
- Bay in set angles, or bow across more facets for a curve
- Lights
- Three, four or five across the run, fixed or opening in any mix
- Posts
- The angled joints between lights, in the same colour as the frames
- Below the glass
- Cill, and the board or brickwork carrying the run
- Colour
- Matched across the whole run inside and out, so it reads as a single window
The colour range is the range of the window you choose rather than anything the shape decides, so a bay is available in the full uPVC foil range or in any RAL colour on aluminium.
Specification choices
Finish the design with your colours, glass and hardware.
Choose your colours, privacy glass and hardware; each guide helps narrow the detail before survey.
Product questions
FAQs about Bow and Bay Windows
Which windows can be built as a bay?
Any window we fit. A bay is a run of frames joined at an angle rather than a window of its own, so casement, flush casement, sliding sash, tilt and turn, and the aluminium casement, flush and heritage windows can all form one.
What is the difference between bow and bay windows?
A bow usually uses several windows to create a curved appearance, while a bay projects more angularly from the property.
Can bow and bay windows improve room space?
They can add usable depth to the window area and bring in more daylight, making the room feel larger and brighter.
Do bow and bay windows need structural checks?
Yes. The existing opening, supports, cill, roof or canopy details should be checked before replacement is confirmed.
Can I choose opening windows within the bay?
Yes. We can combine fixed panes and opening sashes to balance ventilation, views, cleaning and security.
Can they match the other windows?
Yes. Colours, profile style and handle finishes can be coordinated with other uPVC or aluminium windows on the property.
Order process
A clear process from first quote to aftercare.
Four steps. The first one has two ways in: price it yourself online, or have us come out. After that it runs the same either way.
Your price
Price it yourself on the online tool, or book a free consultation and we build the same quote with you. Both run on the same price list, so the figure matches.
Technical survey
Once you go ahead we survey before anything is made. Not a second sales visit: the measurements, thresholds and fixings the factory needs to build it right.
Installation
Fitted by our own installers rather than subcontractors, trained on the systems we sell and working carefully in a house someone lives in. We clear up after ourselves before we leave.
Aftercare
A ten year insurance-backed guarantee through the CPA on new windows and doors, and your FENSA certificate sent direct. Anything afterwards, you ring us, not a call centre.
What Milton Keynes homeowners say
Real reviews from real installations. Every one is public, so you can go and check them yourself.
Stuart Matthew
7 months ago
Fenster have just completed a front door installation on my new property - fantastic job and strongly recommend! The online design tool is great, Perry back at HQ is brilliant as is his communication. Andy, who installed the door, is a top gent and professional. Will definitely be a returning customer.
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Joanna Hayes
3 months ago
Really happy with the service we received from Fensters Windows. Aaron and Shane turned up on time and were both really friendly. They explained any issues as they went along and talked us through the different options, which we really appreciated. They did a great job fitting our new back doors and cleaned up everything afterwards. We also paid exactly what we had originally been quoted, with no unexpected extra costs. Really pleased with our new doors and would definitely recommend Fensters Windows. Thank you Aaron and Shane!
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Digger
3 months ago
We have used Fensters for years on a variety of glazing work, and 2 door installations. They are competitively priced and responsive. They take great care over measuring and specifying the work, giving you a clear quote so you understand what you are getting (thanks Perry!). The fitters are all extremely competent and personable. We had to replace our front door for accessibility reasons, they gave us confidence that our requirements would be met, reproduced the intricate leaded and stained-glass pattern of our old door, and did a quality fitting job (thanks to Johnnie and Shane!). In summary they are our go-to suppliers for all replacement and repair work.
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Silvia Peraro
2 months ago
I had an excellent experience with Fenster Glazing from start to finish. Nick Perry and David managed the initial quote to installation process seamlessly, keeping communication clear, honest, and completely stress-free. When it came to the actual fitting, Zac and Shane did a fantastic job with the installation, working efficiently and leaving everything spotless. The professionalism from the entire team was top-notch, and the final result looks brilliant. I highly recommend them.
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Bernie Raffe
4 months ago
Great service from Fenster Glazing, very happy with our new bi-fold door, glass door and windows (with built-in blinds) There was an issue with the wrong spec of glass provided to them from their supplier, so they had to temporarily board up a door and a window, but this was put right within a few weeks. Recommended, thanks.
Read on Google Zak Jessup 12 Jun 2025Cannot recommend higher! Nick and Perry were really helpful in getting my windows sorted ASAP.
Read on Google Norman Cummings 10 Jun 2025The best service ever, great workmen, very high standard and in the finish, excellent eye to detail.
Read on GoogleOur work
Recent work across the range.
Jobs we have finished recently, fitted by our own installers and photographed the day we finished. They cover the range rather than this product.
uPVC casement window, Loughton
A badly fitted window left by a cowboy builder, replaced with a two-tone Liniar uPVC casement and finished cleanly inside and out.
Read case study
Composite front door and sidelight, Milton Keynes
An anthracite grey composite front door and a full height sidelight, replacing a white uPVC door and a side panel boarded across its bottom half.
Read case study
Secondary glazing, Winslow
Six secondary glazing units in a listed Winslow home, five horizontal sliders and one lift-out, fitted inside the original windows in white aluminium.
Read case studyStart your project
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Where we fit
Bow and bay windows in Milton Keynes and the towns around it.
Each town has its own page: the homes there, what to check before you order, and who to ask about permission.