The AluK 58BW ST HI system delivers exceptional thermal and acoustic performance, with a flexible range. With our slim outerframe and multiple sash options, this system allows you to match any design or project aesthetic
Slimline Aluminium Casements
Performance, Versatility & Style — Tailored for Every Project
A Fully Integrated Window System, Built for Choice
Sash Options:
A timeless, putty-line inspired design with a subtle bevelled edge, the chamfered sash is ideal for both for traditional or heritage-style projects.
Clean, sharp and contemporary. This flat sash is perfect for modern architectural designs that favour minimalism and simplicity.
Designed to replicate the look of classic steel windows, this stepped sash delivers defined sightlines and an authentic industrial aesthetic.
Choose from three high-performance window variants engineered for efficiency, security, and architectural impact.
| Feature | 58BW ST HI |
|---|---|
| Frame Depth | 58mm / 70mm |
| U-Value (Double Glazing) | 1.4 W/m²K |
| Acoustic Rating | Rw 43dB |
| Glazing Thickness | 24–32mm |
| Sightlines (Frame to Vent) | 66mm |
| Opening Types | Casement, Multi-Light, French |
| Aesthetic Options | Heritage / Bay / Contemporary |
| Security | PAS 24 |
| Certifications | Q-Mark, SBD |
FAQ
What’s the difference between the 58BW HI and ST HI versions?
The ST HI version replicates classic steel window aesthetics with slimmer sightlines (66mm) and heritage styling, while the standard HI version offers a broader range of modern configurations.
Can I use these windows in high-rise applications?
Yes. All versions are designed for low and high-rise suitability, with internal or external glazing options and pressure-tested up to Class E2400 wind resistance.
Are these windows compliant with building regulations?
Yes. With U-values from 1.2 W/m²K (triple glazed) and Green Guide A ratings, the range is compliant with Part L thermal performance standards.
Is flush design available on all models?
No. The flush finish is specific to the 58BW HI Flush Casement model, designed for sleek, modern homes with a minimalist profile.
Can these windows be colour-matched to my project?
Absolutely. All models are available in single or dual colours, including anodised finishes, to suit virtually any design palette.
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