The Smart Alitherm 400 is a premium window system that combines modern performance, timeless design and exceptional quality, ideal for both renovation and refurbishment projects.
Part of Smart Architectural Aluminium’s product family, a trusted and experienced fabricator of high-performing aluminium systems, and distributed by BDC Aluminium, Alitherm 400 Windows are expertly designed to suit both residential and light commercial applications.
A favourite among builders and installers for its ease of installation and reliability, and loved by homeowners for its sleek aesthetics and low maintenance, the Alitherm 400 Window system covers all bases.
Modern Efficiency to Older Properties
Performance is one of the more important factors to consider when choosing a window system for renovation projects. Often, fabricators can achieve either the desired look or performance, but not both. This is where Alitherm 400 shines.
Built into every one of our aluminium window systems is our advanced polyamide thermal break technology. It significantly reduces heat transfer through the window, helping renovated homes to stay warmer in the winter and cooler in the summer.
Alitherm 400 complies with current Building regulations, namely Part L, with its 1.4 u-value. This demonstrates the impressive thermal performance and energy efficiency of our aluminium systems.
For builders, this means easy compliance with energy standards for refurbishments without the need for any complex adjustments. For homeowners, reduced energy bills and carbon footprint.

Strength, Durability & Low Maintenance
The natural strength, rigidity and corrosion-resistance of aluminium make it the ideal material choice for windows in areas or properties in high traffic or exposed to the elements.
Despite being relatively lightweight, the sturdiness of the aluminium makes its installation in older structures easier – a key advantage for renovation work. It also won’t rot, warp or swell like timber or uPVC alternatives, making it a much more durable and lower maintenance option.
Design Flexibility and Aesthetics
The Alitherm 400’s slim 70 mm frame depth creates slender sightlines and maximises the glazing area for more natural light. This makes them perfect for creating bright, open interiors. The clean, minimalist frames integrate seamlessly with traditional sash styles or modern casement looks, for added flexibility in design.
To help you meet design specifications, we offer over 200 RAL colours. We even offer dual-colour options, meaning each side of the windows can be finished in a different colour.
With our Alitherm 400 Windows, homeowners enjoy enhanced curb appeal and a light and airy space within. Builders get to work with an adaptable system that meets the diverse needs of their clients.

Designed with Installers in Mind
Alitherm 400 Window systems are engineered for fast, straightforward installation, to help builders and installers save time on site.
The system’s Quick-Glaze bead design features pre-fitted gaskets, simplifying glazing and reducing the need for any adjustments on the day of installation.
What’s not to love? The Alitherm 400 aluminium system from BDC is the perfect solution for both builders and homeowners.
Ready to specify Alitherm 400 for your next refurbishment? Get in touch with our experts today to discuss your next project.