A modern design that maximizes the glazed area is a must in any window system. KS59 casement window has been specially designed to provide a sleek and modern aesthetic to homes or commercial buildings, characterized by its ultra-slim aluminium sightlines of only 70 mm.

This versatile aluminium system gives a distinctive appearance to any property, providing a selection of three sash design options and two outer frames. This range caters to various styles, from a modern and clean look to heritage or crittall-inspired designs.

All these features collectively make the new KS59 an optimal choice for those seeking a cost-effective and fabricator-friendly solution with a timeless and elegant design.

  • Three sash design: flat, stepped or chamfered
  • Two outer frame options: flush or standard
  • U-value as low as 1,4 W/m2K
  • Top and side hung applications
  • Mechanical corner cleats or crimping cleats
  • Wide range of solutions: 90º angle, adjustable bay pole, 20 or 40 mm flush add ons, cills, coupler sections…
Technical information
Air permeability* Class 4
Water tightness* Class 9A
Wind load* Class C5
Thermal insulation Uw** Up to 1,4 W/m2K


* Air/Water/Wind tests according to standard BS6375-1

** Please note: U-Values are dependant on size and glass U-Values. The above are based on a 3 panel door and glass U-Values of 1,1 W/m2K.

Maximun size (top hung): 1200x1500 mm

Maximun size (side hung): 600x1200 mm

Maximum weight: 50 kg

Maximun glazing: 28 mm

Polyamide: 24/32 mm

PAS 24 Security 

Air, wind and water tested to BS6375-1 


KS59 is an oustandingly versatile aluminium system with an ultra-slim sightlines of only 70 mm to maximise glass areas. It provides a large range of sashes and frames design combinations to create stylish and contemporary looks to both new build and refurbished projects. Available in two different design choices: with a stylish and contemporary casementaesthetic, or a new flush frame.


On sites where security and strength are paramount, KS59 system is ideal as tests PAS 24:2012 and BS6375-2-2009 demonstrate.
These important characteristics give confidence when dealing with education and commercial sites where durability is a key consideration.


The KS59 window has been tested in accordance with BS6375-1 2015 for Air, Water and Wind resistance, making it an ideal choice for exposed or remote sites.


KS59 gives versatility thanks to its wide range of sections which include flat, stepped or chamfered options allow for the creation of a spectrum of styles, ranging from modern and minimalist aesthetics to heritage and industrial casement designs. This aluminium system provides an extensive array of accessories and complements, encompassing Georgian bars, cills, trickle vents, bay pole, 90º corner, and flush add-ons of 20 and 40 mm.

Technical manual

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