Optio 58BW TBT HI Window

Beautiful house with tilt before turn black windows

Our tilt-before-turn HI aluminium windows offer exceptional safety and seamless operation

Clean lines and advanced functionality make the 58BW Tilt-before-turn (TBT) HI window a popular choice for new build and refurbishment projects where safety and ease of operation are important.


Offering exceptional child safety and seamless operation, our Tilt-before-turn windows can provide safe opening and ventilation for bedrooms.


The 58BW TBT HI window is a popular choice for medium to high rise properties. Made from high-performance aluminium, this sustainable system is inherently strong yet lightweight. The tilt and turn function also allows for easy cleaning, ideal for rooms above the second floor and above where ease of cleaning is essential.  


  • Certified under the Secured By Design scheme
  • Tested to PAS 24
  • Green guide rated A
  • Integrated deep head profiles for ease of trickle ventilation
  • Unique polyamide thermal break design to improve thermal performance


  • Glazing 24mm – 40mm
  • Available in two frame depths: 58mm and 70mm
  • Available in a range of single or dual colour and anodised finishes
  • Available in the following aesthetics: Bay and Contemporary
  • Available in the following configurations: tilt-before-turn, side hung, bottom hung, fixed light and multi-light
  • Available for Lifetime Homes (LFT)


The 58BW TBT HI is a tried and trusted window system that delivers exceptional performance, functionality and safety.

Low U-values of 1.4 for double glazing and 1.2 for triple glazing, and a Green Guide ‘A’ Rating, make this energy efficient window the ideal partner for both new build and refurbishment projects where warmth and comfort are paramount.

With impressive air, water and wind resistance test figures, this system can withstand extreme weather conditions, keeping your home warm and dry.

Safe and extremely secure, this window system is certified under the Secured by Design scheme, and tested to PAS 24, which means it has been rigorously tested.

The 58BW TBT range is available in several configurations to suit your project: tilt-before-turn, side hung, fixed light, and multi-light. It is also available in two frame depths to suit the thickness of your walls: 58mm and 70mm.

As with all AluK aluminium systems, the 58BW Casement is available in single or dual colour powder coating, texture and anodised finishes.

Standard Technical Data HI technical data
U value W/m²K 1.3 W/m²K -1.5 W/m²K 1.2 W/m²K -1.4 W/m²K
Window energy rating B-C B-C
BRE Green Guide rating A rated A rated
Air tightness (Pa) Class 4 (600 Pa) Class 4 (600 Pa)
Water tightness (Pa) Class 8A (450 Pa) Class 8A (600 Pa)
Wind load (Pa) Class E2400 (2400 Pa) Class E2400 (2400 Pa)