Alitherm 400 Contemporary Aluminium Windows
Slim, modern aluminium windows with outstanding energy efficiency, security, and durability professionally supplied Nationally and installed across the north of England
Made to Measure Aluminium Windows
Alitherm 400 Contemporary Aluminium Windows
Slim, modern aluminium windows designed for comfort, security and lasting performance.
Alitherm 400 combines clean architectural styling with thermally efficient aluminium frames, making it an excellent choice for home extensions, new builds and contemporary renovations. Manufactured to your project’s requirements, these windows offer versatile designs, attractive finishes and dependable everyday performance.
Made to measure, delivered nationwide across the UK, with specialist installation available across the North of England.
Cradle to Cradle Certified
A commitment to more responsible material choices and circular design, with a focus on keeping valuable materials in use through reuse and recycling.
Performance & Design
Alitherm 400 Key Features
Designed to deliver thermal efficiency, security and a wide choice of contemporary finishes.
Excellent Thermal Efficiency
High-performance glazing options, with A+ Window Energy Rating achievable on suitable specifications.
Advanced Thermal Breaks
Innovative polyamide thermal break technology helps minimise heat transfer through the frame.
Building Regulations
Designed to support current building requirements when correctly specified and installed.
Enhanced Security
Security-focused design with PAS 24:2016-approved configurations available.
Dual-Colour Finishes
Different colours can be specified for the inside and outside of your windows.
Extensive Colour Choice
Choose from a wide range of colours and finishes to suit your property.
About The System
What Are Alitherm 400 Contemporary Windows?
Alitherm 400 is a thermally broken aluminium window system suited to modern homes and renovation projects. Its contemporary profiles combine practical insulation and security features with the strength and durability of aluminium, without the appearance of bulky frames.
Ideal for a Wide Range of Projects
The Alitherm 400 contemporary window system
Designed for performance
Alitherm 400 uses advanced polyamide thermal break technology to create an insulating barrier between the inside and outside of the frame. This improves thermal performance, helps retain heat and supports compliance with current building regulations. The system is also designed to deliver excellent weather resistance, everyday durability and dependable home security.
Performance highlights
- Thermally broken aluminium frame
- Compliant with current Building Regulations
- PAS 24 security accreditation
- Suitable for double glazing and high-performance sealed units
VIEW THE COMPLETE CONTEMPORARY GLAZING COLLECTION HERE
Alitherm 400 Contemporary Windows
”Fantastic company, great product and extremely helpful throughout.”
Helen Westwell – Kendal, Cumbria
Window Styles Available
Alitherm 400 can be manufactured in a wide range of configurations to suit your home:
- Side-hung casement windows
- Top-hung windows
- Fixed picture windows
- Combination windows
- Large format glazing
- Flush or chamfered profiles
Whether you want a single replacement window or a full house transformation, the system is highly flexible.
Marston Lodge Farm – Vale of York
Due to sensitive planning restrictions the development required the retention of existing timber glazing to one of the properties.
As such the owners needed to ensure that new glazing to the remaining properties fully complied with conservation conditions and worked in harmony with the character of the buildings.
The local Council accepted the use of Marlin’s thermally efficient and secure Alitherm 400 windows.
COLOURS AND GLAZING
Your windows should work as hard visually as they do technically. Alitherm 400 is available in a wide range of durable powder-coated finishes, including dual-colour options for different internal and external looks. Combine your chosen frame finish with high-performance glazing to achieve the right balance of light, privacy, solar control and energy efficiency for your project.
the windows and doors look fantastic. Excellent service from initial contact through to delivery and beyond:-)”
Why Choose Marlin?
Made for Your Project
Every window is manufactured to your required sizes and specification for a precise fit and a cleaner finish.
Quality at Every Stage
Our manufacturing process is carefully controlled to maintain consistent standards from order to delivery.
Support You Can Rely On
From your first enquiry through to installation and aftercare, we focus on clear advice, careful service and a result you’ll be happy to live with.
Download the Alitherm 400 Window & Door Brochure
Alitherm 400 brochure
Ready to transform your home?
Get a made-to-measure quote for your Alitherm 400 Contemporary Windows today. Our team will guide you through sizes, styles and glazing options to find the perfect fit for your home.
Or call us on 01535 603909 to speak with our team.
Frequently Asked Questions
If you require any support, please don’t hesitate to review our FAQs below or drop us a message on our contact form here
What are Alitherm 400 Contemporary Windows made from?
Alitherm 400 windows are crafted from high-quality thermally broken aluminium. This material offers excellent strength, durability, and slim sight lines, while maintaining top energy efficiency through an internal thermal break that reduces heat loss.
Are Alitherm 400 windows energy efficient?
Yes. With thermally broken frames and high-performance glazing, they meet current UK energy standards and help reduce heat loss.
Can Alitherm 400 windows be used in both modern and traditional homes?
Yes. These windows are designed with versatility in mind. Their clean, slim profiles suit contemporary architecture, while the flush casement and chamfered options also complement more traditional or heritage-style homes.
How do I maintain and clean aluminium windows like the Alitherm 400?
Aluminium windows are low-maintenance. Regular cleaning with warm soapy water and a soft cloth is usually enough. Unlike timber, they won’t warp, rot, or need repainting, just an occasional check of seals and moving parts to ensure optimal performance.
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