Alitherm 300 Casement Windows

Alitherm 300 casement windows by Smart offer a sleek, reliable, and energy-efficient solution for both contemporary and traditional properties. Designed with slim, elegant sightlines and manufactured in-house by Direct Trade Windows, these windows are ideal for homeowners, architects, and trade professionals looking for the perfect balance of performance, value, and style. The system is suitable for both side-hung and top-hung openings, making it flexible for a wide range of installations.

Built using thermally broken aluminium profiles, Alitherm 300 casement windows deliver excellent insulation and weather resistance, while maintaining a refined, modern appearance. Available in a wide range of RAL colours and finishes—including dual colour options—they’re custom-made to your exact specification. Backed by our expert technical support and reliable service, they represent a long-term investment in quality and comfort.

Key Features:

• Thermally broken aluminium: Excellent energy efficiency and low U-values
• Versatile configurations: Side-hung and top-hung casement options
• Slim aesthetic: Modern, clean sightlines to suit all property styles
• Custom finishes: Available in any RAL colour, including dual colour options
• Secure and durable: High-performance hardware and multi-point locking
• In-house manufacturing: Built to order with short lead times and full quality control