HolzAlu

HolzAlu refers to wood-aluminium composite construction, most commonly used in windows, doors, and façades. It combines a wooden interior frame or sashes with exterior aluminium cladding. The arrangement aims to retain wood’s insulation and aesthetics while providing a weather-resistant, low-maintenance exterior. HolzAlu products are widely installed in residential and commercial buildings, particularly in Europe.

Construction typically uses a timber core with a deliberate thermal break and insulation in the frame. Exterior aluminium protects the wood from rain, UV, and pollution, while the interior wood can be finished with varnish or paint. Most variants include double or triple glazing and sealed joints to improve energy efficiency.

Benefits include durable exterior, reduced maintenance, and design flexibility; inner wood offers warmth and good insulation. Drawbacks include higher upfront cost compared with pure wood or aluminium, and the need for proper maintenance of the wood interior to prevent moisture issues.

Manufacturers supply HolzAlu as windows, doors, or curtain-wall elements, with various timber species, aluminium finishes, and glazing options. The concept is popular in German-speaking regions and is increasingly used globally.

Environmentally, the system combines renewable wood with recyclable aluminium and, with proper maintenance, offers long service life. Modern HolzAlu products emphasize durability, energy efficiency, and design versatility while balancing cost considerations.