Casement
Bespoke uPVC casement windows (aluminium available) built with Eurocell profiles, double or triple glazing and premium glass from Martin Dales and Glasscraft.
Browse technical options
Browse our range of colours and glazing options or download our brochure for free to view the specifications of these windows in full.
- Details/Features
- Specifications
- Glazing & Security
- Colours
- Downloads
Technical specifications overview
Key specs for our bay & bow windows. If you have further questions, please don't hesitate to get in touch.
Contact Us| Feature | Specification |
|---|---|
| Profile depth | 70mm Logik / 75mm Modus |
| Glazing | Double 28mm / Triple 36–44mm |
| U-values | Down to 0.7 W/m²K with triple glazing |
| Energy rating | Up to A++ |
| Colours | 30+ foil finishes |
| Security | Multi-point locking, Secured by Design |
| Glass options | Low-E, toughened, laminated |
Glazing and security performance
Units are available in double and triple glazing with Low-E coatings for improved efficiency and reduced energy costs. All units are internally beaded with multi-point locking systems for stronger security performance.
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Colour range availability
Choose from a wide selection including anthracite grey, white, black, oak and chartwell green, suitable for both modern and traditional bay window installations.
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EUROCELL white ash
EUROCELL golden oak
EUROCELL black ash
EUROCELL anthracite grey
EUROCELL Chartwell gren
EUROCELL agate grey
Irish Oak
RAL option
Technical downloads and support
Access technical brochures, installation guides and product specifications to support accurate quoting and efficient installation planning.
Contact UsWhere bay windows are used
Bay and bow windows are widely specified for domestic living rooms, creating extra seating areas and improved natural light. They are also suitable for converted buildings including clinics or offices where frontage appeal and light intake matters.
In commercial adaptations such as a dentist waiting room or nursery, both bay and bow windows support ventilation, daylight and improved space perception for occupants and visitors.
Trusted trade supply partner
We are a family-run manufacturer in Leeds with approaching 80 years of combined experience. Our team provides fast trade quotations, typically within 24 hours, with delivery in around two weeks.
We supply Secured by Design compliant systems with consistent quality control and responsive support for installers across Yorkshire and beyond.
Common trade questions on bay windows
Quick answers for installers and builders specifying bay and bow windows across Leeds and the surrounding areas.
Our bay windows can achieve U-Values down to 0.7 W/m²K with triple glazing. Double glazing options are also available for cost-effective installations while still meeting current energy efficiency requirements for most residential and commercial projects. With double glazing, you’re largely looking at a U-Value of around 1.2.
Yes, our systems are suitable for refurbishment and new build installations. Eurocell profiles provide structural stability for main walls of a building while supporting a wide range of configuration and glazing options.
All units include multi-point locking systems and Secured by Design accreditation as standard. Internally beaded glazing improves security performance, giving installers and end users added peace of mind on all installations.
We offer over 30 foil finishes including anthracite grey, white, oak and chartwell green. These support both modern bay windows and traditional property styles across Leeds and Yorkshire.
We typically deliver within two weeks depending on specification. Quotes are usually returned within 24 hours, supporting fast turnaround for fitters and builders managing time-sensitive projects.
How we work with the trade
Our Process
Initial quote
Send us your sizes online or over the phone. We turn most trade quotes around within 24 hours, and there is no obligation to proceed.
Conversation
We talk through the priorities for you or your client, be it design, thermal performance, security, colour finish, glazing, or locking.
Manufacturing
We manufacture in-house at our Morley facility using Eurocell uPVC profiles, DoorCo composite slabs and Alunet aluminium systems. Typical lead time is two weeks.
Bespoke build, testing and supply
Every frame is made to your exact sizes and quality-checked before despatch. Supply only as standard, full installation available on request.
What fellow trade professionals say about us
Honest feedback from the installers, builders and double glazing companies we supply day in, day out.
"Had both front and back stable doors fitted recently, and I have to say the men that came to fit them were really good, pleasant, efficient and did a great job! I am rea...
“Had both front and back stable doors fitted recently, and I have to say the men that came to fit them were really good, pleasant, efficient and did a great job! I am really pleased with my doors and the way the men conducted themselves; they are a credit to Alpine – thanks again.”
Carol Marshall
Carol Marshall
"I can’t thank the team at Alpine enough for all of the hard work on your build. They were great from the start, being really helpful through the quote process and in adv...
“I can’t thank the team at Alpine enough for all of the hard work on your build. They were great from the start, being really helpful through the quote process and in advising. The fitting team worked so hard to make sure everything was perfect, and nothing was too much trouble. We are so happy with Alpine. The results really speak for themselves, and we would not hesitate to recommend them to anyone!”
Kate Oakes
Kate Oakes
"We recently renovated a small cottage and needed to consider the traditional look and feel of the property, Alpine Windows and Doors were brilliant, listening to our req...
“We recently renovated a small cottage and needed to consider the traditional look and feel of the property, Alpine Windows and Doors were brilliant, listening to our requirements, we ended up with 6 sash windows and a new composite door all in a non standard colour, which was no problem. from placing the order to the completion of the installation nice and smooth, 5 weeks time frame, fitted perfectly with our project, would highly recommend”
Tom Crowe
Tom Crowe
"Excellent service from start to finish. They made the process from colours to design easy, nothing was too much trouble. Lovely polite staff and fitters. Fitters turned ...
“Excellent service from start to finish. They made the process from colours to design easy, nothing was too much trouble. Lovely polite staff and fitters. Fitters turned up on time and finished to an exceptional standard (I am a perfectionist!) left my home clean and tidy and removed all old frames and doors. Couldn’t fault them at any stage and would highly recommend them. I would give more than 5* if I could.”
Sarah Wood
Sarah Wood
"Peter at Alpine has done the windows and doors at both our offices and my home. The service was very professional, fast and competitive price wise. I had a combination o...
“Peter at Alpine has done the windows and doors at both our offices and my home. The service was very professional, fast and competitive price wise. I had a combination of Aluminium bi folds and French doors with UPVC windows. I cannot fault the quality. Very happy to recommend for both domestic and commercial projects.”
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