Ideal for both residential and commercial applications, this thermally improved variant of AluK’s popular BSF70 system provides enhanced energy efficiency, robust structural strength and flexible configuration options.
Fabricated by Arkay using genuine system components, the BSF70 HI bi-fold combines slim, modern sightlines with proven performance — making it a dependable choice for installers, developers and architects seeking a premium, compliant aluminium folding system.
The BSF70 HI maintains the clean AluK aesthetic with slim meeting stiles and refined hardware options, helping create bright, open internal spaces with minimal visual interruption.
Precision-engineered hardware and strong rollers deliver consistent, smooth operation — ideal for high-traffic residential areas and commercial access points.
Open-in and open-out options
Multiple panel configurations from 2 to 7 leaves
Inline or traffic door options for everyday convenience
This flexibility enables custom layouts to suit a wide variety of openings and architectural requirements.
Enhanced insulation performance for meeting modern building requirements, particularly in replacement and new-build residential markets.
Standard threshold
Low threshold
This allows the system to meet accessibility requirements or deliver seamless transitions to outside spaces.
Accepts 24–40 mm glazing, enabling a range of double- or triple-glazed units to boost thermal efficiency, security or acoustic performance.
| Specification | BSF70 HI Value |
|---|---|
| U-value (double glazing) | From 1.6 W/m²K |
| U-value (triple glazing) | From 1.4 W/m²K |
| Air tightness | Class 4 (600 Pa) |
| Water tightness | Class 9A (600 Pa) |
| Wind load resistance | Class AE2400 (2400 Pa) |
| Security | PAS 24 certified |
| Max vent weight | 130 kg |
| Max panel height | 3000 mm |
| Glazing thickness | 24–40 mm |
The HI (High Insulation) variant features enhanced thermal performance, helping installers meet modern building regulations while maintaining the same slim sightlines and flexible configurations of the standard system.
The system supports 24–40 mm glazing, allowing installers to use double or triple glazing depending on the thermal or acoustic requirements of the project.
Yes — the BSF70 HI can be specified to meet PAS 24 security requirements, making it suitable for new-builds and projects needing compliant entrance solutions.
The system handles panel heights up to 3000 mm and vent weights up to 130 kg, enabling large openings and a wide range of multi-panel configurations.
Yes — the system offers standard, deep, low and ultra-low threshold options, giving installers flexibility for accessibility requirements and seamless indoor–outdoor transitions.
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