Passive house construction demands the highest standards in thermal performance, airtightness, and energy efficiency. Among all building envelope components, windows remain the most critical — and most challenging — element in meeting strict passive house criteria. The ALPES AW90 Passive Window addresses this challenge head-on with its innovative dual-matrix eight-layer sealing system, delivering a K-value as low as 1.3 while ensuring exceptional airtightness, weather resistance, and long-term durability.
Dual-matrix sealing is an advanced window sealing architecture that employs two coordinated sealing matrices working in tandem rather than relying on a single gasket barrier. The first matrix handles continuous airtightness and thermal insulation, while the second matrix manages dynamic weather events — rain, wind pressure, and temperature fluctuations. This two-tier approach creates redundant protection where one system compensates for the other's limitations, resulting in a far more reliable seal than traditional single-gasket designs.
The concept draws from building science principles proven in Passivhaus-certified construction worldwide. Studies on building envelope performance consistently show that single-seal systems degrade faster under real-world conditions, especially where windows meet walls or where sashes meet frames. Dual-matrix design eliminates these weak points by distributing sealing responsibilities across specialized layers.
The AW90 Passive Window from ALPES takes dual-matrix sealing to the next level with a comprehensive eight-layer sealing configuration. Each layer serves a specific function, working together to block air infiltration, prevent water penetration, reduce noise transmission, and maintain consistent thermal performance.
Passive house certification requires windows to meet extremely strict thermal performance targets. With a thermal K-value of just 1.3 W/(m²·K), the AW90 comfortably exceeds these requirements. But low U-value alone is not enough — airtightness is equally critical. The dual-matrix system ensures air infiltration rates well below the Passivhaus threshold of 0.6 air changes per hour at 50 Pascals.
The inner sealing matrix focuses on permanent airtightness and thermal continuity. It uses dense compression gaskets bonded with injection-molded structural adhesive to create an uninterrupted air barrier along the entire sash-frame interface. This inner matrix also works in conjunction with the PA66GF25 multi-chamber thermal break strips, ensuring the sealing system itself does not create thermal bridges that would degrade overall performance.
The outer sealing matrix handles dynamic environmental loads. Extended and composite sealing strips form the first line of defense against wind-driven rain, while the labyrinth-style threaded strips slow any water that manages to pass the outer defense. Drainage channels within the frame then direct any captured water back to the exterior before it can reach the inner air barrier. This staged approach means the inner seal rarely faces direct water exposure, dramatically extending its service life.
K-value of 1.3 drastically reduces heating and cooling loads, cutting annual energy bills significantly.
Eliminate cold drafts near windows and maintain uniform indoor temperatures throughout the year.
Eight-layer sealing combined with insulated glass dramatically reduces outdoor noise infiltration.
Prevent condensation, mold growth, and water damage with properly staged water management layers.
For builders and architects, the AW90 simplifies quality assurance on site. The pre-engineered sealing system is factory-assembled and tested, reducing the risk of installation errors that commonly compromise field-applied window flashing and sealing. The tilt and turn windows design also allows for easy inward cleaning and emergency egress, adding practical value that passive house projects often overlook.
Behind the AW90's sealing performance stands ALPES's comprehensive approach to window engineering. The frame is constructed from 6060-T66 grade aluminum profiles with a 1.8mm wall thickness — meeting and exceeding new national standards for structural rigidity. This robust base ensures the sealing system remains properly compressed even under wind loads and thermal expansion cycles.
The window also features 360° locking point distribution around the full perimeter, ensuring uniform compression of all eight sealing layers. This is a critical detail often missed in lesser-quality windows — uneven compression means some seal sections do virtually nothing while others wear prematurely. ALPES addresses this with hardware from Winkhaus, a German manufacturer with 169 years of precision engineering experience.
Durability testing further validates the design. The AW90 has passed 240-hour salt spray corrosion resistance testing and demonstrates 5,000 Newtons of shear resistance strength. For homeowners in coastal areas or harsh climates, these test results translate directly to decades of reliable, maintenance-free performance.
The AW90 Passive Window's dual-matrix eight-layer sealing system represents a significant advancement in aluminum window technology. By combining specialized inner and outer sealing matrices with precision-engineered frame construction and premium European hardware, ALPES has created a product that not only meets passive house standards but sets a new benchmark for what aluminum windows can achieve.
Whether you are designing a net-zero energy home, a luxury villa, or a commercial project demanding the highest performance standards, the AW90 delivers proven thermal performance, exceptional airtightness, and the long-term durability that only a well-engineered dual-matrix sealing system can provide.
As a leading casement window manufacturer in China, ALPES offers a full range of high-performance aluminum windows and doors. With a 100,000 m² production facility across Foshan and Zhaoqing, the company serves luxury residential and commercial projects worldwide. Contact ALPES today to discuss how the AW90 Passive Window can elevate your next project.
