ST90 Window System
Versatile Design
Our ST90 window system represents a key milestone in the evolution of modern fenestration. It directly meets the growing thermal performance requirements of architects, design teams and clients. The system achieves whole-window Uw values as low as 0.71 W/m²K, offering excellent energy efficiency from the start.
We designed the ST90 using the latest thermally efficient technology, creating a secure and highly insulated barrier that reduces heat loss. Because of this, the system delivers a modern, energy-focused and visually clean solution for a broad range of projects.
The ST90 also shares the same sightlines as the rest of our ST suite. This consistency allows you to value-engineer a project from elevation to elevation, or floor to floor, while staying within specification, budget and design requirements.
Durability
The ST90 uses materials chosen for their strength, long service life and recycling potential. These components support a maintenance-free lifespan of up to 30 years. As a result, the system suits commercial, institutional and residential developments that require reliable long-term performance.
Eco-Friendly
The ST90 also carries strong environmental credentials. We use recycled aluminium and polyamides throughout the system, with up to 50% recycled content depending on the configuration. Therefore, the ST90 is an ideal choice for architects and designers who focus on sustainability and responsible material selection.
Opening Possibilities
The ST90 offers a wide range of opening options. These include tilt and turn, lifetime-homes tilt and turn, bottom-hung open-in, side-hung and top-hung open-out, bottom-hung open-out (hopper), and side-hung open-in.
Each configuration includes a multi-point, wrap-around locking system for added security. In addition, the flexible locking mechanism supports larger sash sizes, giving designers more freedom on complex projects.
Glazing Opportunities
The ST90 supports triple or quadruple glazing from 38 mm to 62 mm. This flexibility helps improve acoustic performance, reduce heat loss and lower noise levels in both living spaces and work areas. As a result, the system provides strong thermal and sound insulation benefits.
Finish
You can choose to have the ST90 fully fabricated in our facility or supplied in stock lengths for project-based fabrication. The system is available in single or dual colour, finished to Qualicoat Powder Coat standards. With minimal maintenance requirements and a long service life, the ST90 offers a dependable solution for both residential and commercial applications.
You can download our the ST90 Brochure here or access the manual by registering for our Technical Library above.
- Designed for the ultimate in thermal efficiency.
- Whole window Uw value as low as 0.78 W/m²K.
- Tested to Pas 24 standards.
- Elements of the window were chosen for their end of life recycling.
- Tested to EN12101 smoke ventilation.
- Single or dual colour available.
- Triple or quadruple glazing up to 62mm in thickness.
- New low conductive polyamides used in the window assembly.
| Frame Depth | 90mm | |
| BS 6375-1 | Air Tightness: | Class 4 - 600 Pa |
| BS 6375-1 | Water Tightness: | Class EN1050 - 1050 Pa |
| BS 6375-1 | Wind load resistance: | Class 5 up to 3000 Pa |
| BS 6375-2: | Operating forces: | Class 1 |
| BS 6375-2: | Mechanical strength: | Class 3 |
| BS 6375-2: | Repeated opening & closing (30,000): | Class3 (Heavy Duty) |
| PAS 24: | Security classification: | Certisecure |
*Whole window U values are a combination of the frame and glazing thermal performance and as such will vary with the specification of glass utilised. Please consult with the APA technical team for more specific performance information.
