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Smart Systems, Alitherm 400

Premium aluminum designs with exceptional strength

Smart Systems Alitherm 400 - High Performance Aluminium Systems


The Alitherm 400 range by Smart Systems offers a comprehensive selection of high-performance aluminium windows and doors, meticulously engineered to meet the demands of both residential and light commercial applications. This system harmoniously blends aesthetic versatility with superior thermal efficiency and robust security features.



Key Features

  • Design Flexibility The Alitherm 400 system provides a variety of sash options, including standard, slimline, flush, and heritage styles, allowing for seamless integration into diverse architectural designs.

  • Innovative Glazing System Incorporating co-extruded gaskets in sashes, outer frames, and Smart Quick-Glaze Beads, this design simplifies fabrication and installation processes, enhancing overall efficiency.

  • Tilt-Turn Window Option The system includes a tilt-turn window configuration, offering versatile ventilation and ease of cleaning, catering to modern living requirements.

  • Thermal Efficiency Fully compliant with the latest amendments to Document L of the Building Regulations, the Alitherm 400 system ensures excellent thermal performance, contributing to energy savings.

  • Enhanced Security Approved to PAS 24:2022 standards, the system provides heightened security features for both windows and doors, ensuring peace of mind.

  • Extensive Colour Options Available in a wide array of colours, the system allows for personalized aesthetics to match any design preference.



Technical Specifications

  • Frame Depth: 70 mm

  • Glazing Options: Accommodates glazing units of 24, 28, 32, 36, 40, and 45 mm thicknesses.

  • Maximum Dimensions:Side Hung Windows: 864 mm (width) x 1,400 mm (height)
    Top Hung Windows: 1,400 mm (width) x 1,400 mm (height)
    Fixed Windows: 2,100 mm (width) x 2,100 mm (height)
    Tilt-Turn Windows: 1,200 mm (width) x 2,100 mm (height)

  • Thermal Performance: Achieves U-values as low as 1.4 W/m²K, contributing to energy efficiency.

  • Weather Performance:Air Tightness: Class 4
    Water Tightness: Class AE2400
    Wind Resistance: Class 2000+



Key Benefits

  • Aesthetic Versatility: With a range of sash styles and an extensive colour palette, the Alitherm 400 system can be tailored to complement any architectural design, enhancing the visual appeal of both new builds and refurbishment projects.

  • Energy Efficiency: The system's advanced thermal break technology and compliance with current Building Regulations ensure optimal thermal performance, leading to reduced energy consumption and lower utility bills.

  • Enhanced Security: Meeting PAS 24:2022 standards, the Alitherm 400 provides robust security features, offering homeowners and occupants increased safety and peace of mind.

  • Ease of Installation: The innovative co-extruded gaskets and Quick-Glaze Beads simplify the fabrication and installation process, reducing time and labor costs for installers.

  • Low Maintenance: Constructed from high-grade aluminium with durable finishes, the system requires minimal maintenance, ensuring longevity and sustained aesthetic appeal.



The Alitherm 400 range stands as an exemplary choice for those seeking a harmonious blend of style, performance, and security in their window and door solutions. Its comprehensive design and technical attributes make it a preferred option for a wide array of building projects.

Smart Systems, Alitherm 400 FAQ

Who makes Alitherm windows?

Alitherm windows are manufactured by Smart Systems, a leading UK-based designer and supplier of high-quality aluminium window, door, and curtain wall systems. Established in 1981, Smart Systems is known for its innovative and energy-efficient solutions, including the Alitherm range, which combines aesthetic versatility with outstanding thermal and security performance.

What do aluminium windows cost?

The cost of aluminium windows in the UK varies based on factors such as size, style, glazing options, and supplier. Here's a breakdown of average prices:

  • Standard Aluminium Windows Typically range from £350 to £600 per window, with an average cost around £475

  • Casement Aluminium Windows Prices start at approximately £210, with an average cost around £605

  • Sash Aluminium Windows Generally more expensive, averaging about £910 per window

  • Tilt and Turn Aluminium Windows These typically cost around £755 on average

While aluminium windows are generally more expensive than uPVC alternatives, they offer benefits such as enhanced durability, slimmer frames, and a modern aesthetic. To obtain an accurate estimate tailored to your needs, it's advisable to consult with local suppliers and obtain multiple quotes.

What thickness of aluminium for windows?

The Alitherm 400 aluminium window system features a frame depth of 70 mm, providing a robust and thermally efficient profile suitable for various applications.

Which is cheaper uPVC or aluminium windows?

uPVC windows are cheaper than aluminium windows.

How many years do aluminium windows last?

Aluminium windows typically last 20 to 45 years or more, depending on the quality of the materials, installation, and maintenance. High-quality, powder-coated frames with proper care can even exceed 50 years, making them a durable and long-lasting option.

Do aluminium windows last longer than uPVC?

Yes, aluminium windows generally last longer than uPVC windows. Aluminium windows can last 20 to 45+ years, while uPVC windows typically last around 20 to 30 years. Aluminium’s durability, resistance to warping, and weatherproofing contribute to its longer lifespan, especially with minimal maintenance.

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Cutting-edge design and outstanding thermal efficiency

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Smart Systems, Alitherm 400

Premium aluminum designs with exceptional strength

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