Cellular glass is a perfect thermal insulation for outside walls after rendering with natural hydraulic lime mortars. These kind of systems are known in Europe as ETICS (External Thermal Insulation Composite System). For each system, the building company needs to find an ETA to be able to deliver the normal guarantee.

The ETA (European Technical Assessment) was requested by Arte Constructo, Belgium and can be applied on all kind of cellular glass boards equivalent with GLAPOR cellular glass. The rendering products are Unilit 15P2, Unilit 65M and Unilit 65F. The mineral adhesive to adhere the cellular glass boards on the wall is Unilit K/2. These mortars are produced at Tassullo, Italy.

After the hygro-thermal testing, the system did not show:

• blistering or peeling of any finishing
• failure or cracking associated with joints between insulation product boards or profiles fitted with the ETICS,
• detachment of render,
• cracking allowing water penetration to the insulation layer.

As a consequence, this system became approved and is now used for several years without important complaints.