Optio 58BW ST HI Window


Why Choose Our AluK 58BW ST HI Windows?

Designed to replace and complement existing steel windows, the range has been specifically developed for use on buildings where steel windows have traditionally been fitted. The slim sightlines allow for an easy match to existing windows, making it ideal for heritage, listed buildings and steel window replacements.

The system also includes hardware that is sympathetic to traditional steel window designs, perfect for planning permissions in conservation areas.

Look Of Steel, Benefits of Aluminium

The range is available in a wide range of standard and RAL colours. Anodised finishes are also available, with marine grade guarantees on request. The 58BW ST HI profiles feature traditional square sections and sightlines of just 43mm in a fixed light. There are four different sash profiles to achieve design and planning permission requirements.

Available in a wide range of styles, including top-hung, side-hung, bottom-hung, fixed light and multi-light, the system cleverly replicates the narrow sight lines associated with steel windows whilst providing superior performance and security. This range is certified under the Secured By Design scheme and fully PAS 24 tested for complete peace of mind.



Exceptional Performance

With excellent air, water and wind resistance test results, this system can withstand the worst of British weather. The 58BW ST HI offers high thermal efficiency with U-values as low as 1.4 for double-glazed and 1.1 for triple-glazed, ensuring your property is warm and comfortable.

The 58BW ST HI windows accommodate up to 32mm glazing units for thermal and acoustic performance.

Technical performances

  Standard technical data HI technical data
U value W/m²K 1.2 W/m²K - 1.5 W/m²K 1.1 W/m²K -1.4 W/m²K
Window energy rating A-B A-B
Air Permeability Class 4 (600 Pa) Class 4 (600 Pa)
Water tightness (Pa) Class 9a (600 Pa) Class E1500 (1500pa)


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