With our slim outerframe in either a 58mm or 70mm frame depth, and multiple sash options, the AluK 58BW ST HI system allows you to mix and match to create different design aesthetics whilst delivering exceptional thermal and acoustic performance.
Slimline Aluminium Casements
Performance, Versatility & Style — Tailored for Every Project
Slimline Aluminium Casements
Performance, Versatility & Style — Tailored for Every Project
A Fully Integrated Window System, Built for Choice
Choose between 3 different 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. This is our go-to standard sash option.
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.
Specification
| Feature | 58BW ST HI |
|---|---|
| Frame Depth | 58mm / 70mm |
| U-Value (Double Glazing) | 1.4 W/m²K |
| Glazing Thickness | 24–32mm |
| Side Hung Max Sizes | 736 x 1436 mm |
| Top Hung Max Sizes | 1436 x 1336 mm |
| Opening Types | Casement, Multi-Light, French |
| Aesthetic Options | Heritage / Bay / Contemporary |
| Security | PAS 24 Option |
| 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, while the standard HI version offers a broader range of modern configurations better suited for commercial projects.
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 (2400 Pa) wind resistance.
Are these windows compliant with building regulations?
Yes. With U-values from 1.1 W/m²K (triple glazed), the range is compliant with Part L thermal performance standards.
Do you offer a flush model?
Yes. Check out our 58BW HI Flush Casement page, designed for use in sleek, modern homes with a minimalist profile.
What window handle options do you have?
We offer our standard modern handles, monkey tail and pair drop handles. Our handles are available in black, grey, white, silver, chrome and gold.
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