In façade design, passive fire protection must perform over time under real-world building conditions — not just in laboratory testing.
This is especially important in curtain wall construction, where façades must accommodate movement caused by wind loads, thermal expansion, and structural deflection. In these applications, a firestop or perimeter fire barrier must do more than fit properly at installation. It must maintain an effective seal over time as the building moves.
That’s where Lamella technology offers a distinctly different solution.
The performance of passive fire protection depends on more than fire resistance alone. It must also maintain proper form, fit, and compressibility throughout the life of the system.
Some conventional stone wool solutions use a horizontal fiber structure. While stable, this configuration can limit the material’s ability to accommodate repeated lateral compression over time. As movement and compression continue, internal fiber bonds may begin to break down, reducing the product’s ability to recover and potentially allowing gaps to form between the fire protection and the façade or slab edge.
In curtain wall systems, where movement is expected, that loss of recovery can become a critical performance issue. Passive fire protection must remain tightly fitted between the façade and the floor slab or adjacent construction, maintaining integrity as those elements move relative to one another. If the material cannot flex, recover, and sustain contact, the long-term effectiveness of the seal may be compromised.
Siderise® developed its proprietary Lamella technology to address these real-world performance demands. Instead of using a conventional horizontal fiber structure, Siderise Lamella is manufactured from a specially formulated stone wool with vertically oriented fibers. This vertical orientation enables the product to better withstand lateral compression and recover more reliably from movement.
Accelerated aging tests conducted in accordance with EOTA Technical Report 024 demonstrated that Siderise Lamella can undergo repeated lateral compression without loss of recovery or flexibility.
Lamella also provides practical installation advantages. The integrated foil facing is clearly marked top and bottom, and because the fibers are already vertically oriented, the risk of installation error is significantly reduced.
Traditional solutions may also require field-applied spray coatings, with insulation cut and compressed onsite before being sealed using an elastomeric compound. Because Siderise products are pre-compressed at the factory, the Lamella material and applied foil scrim provide a high level of fire resistance without the need for an additional wet seal. As compression is applied, the facing visibly wrinkles, providing installers with a clear visual indication that the product has been installed correctly.
Siderise Lamella is designed to maintain form, fit, and integrity in building envelope applications where movement is inevitable. In curtain wall systems, where even small gaps can have significant consequences, the ability to move with the building is a critical performance requirement.
Learn more about the innovation behind Lamella at Siderise US
