Manufactured Materials: Vacuum Insulation Panels (VIPs)
Vacuum insulation panels are innovative products whose use requires specifc considerations because of their special characteristics. They are subject to Technical Appraisal (ATec) or Technical Experimentation Assessment (ATEx) procedures.
Vacuum insulation panels (VIPs) are insulation materials in which the gas or air is replaced by a partial vacuum, giving them thermal insulation properties four times better than conventional insulation materials.
To maintain the vacuum and reduce moisture transmission, the material (amorphous silica) is inserted in an airtight metal enclosure. A product’s thermal performance depends on the integrity of its enclosure, which must be protected during storage and installation. Note: Performance is weakened at the edges because of the continuity of the enclosure, which includes a heat-conducting metal layer (border’s thermal bridges).
La performance thermique du produit dépend de l'intégrité de son enveloppe qui doit être protégée lors du stockage et de la mise en œuvre du produit. Remarque : cette performance est affaiblie sur les bords du fait de la continuité de l'enveloppe qui comporte une couche métallique conductrice de la chaleur (ponts thermiques périphériques).
Guidelines for use
The VIP must be protected from protruding or sharp elements on the wall or liner system which could damage the panel. Since the panels must not be cut or pierced, the layout has to be optimized to obtain the maximum area covered by the VIP. Similarly, the panels must be held in place mechanically using methods that do not compromise the integrity of the enclosure (for example, bonding). The junctions between building elements are caulked with “conventional” insulation. The installation method can induce thermal bridges, for example, the insertion of metal fxing in the wall.
For internal insulation, a vapor barrier system is generally recommended to protect the junctions between panels or through the conventional insulation.
An air space is created between the internal facing and the vapor barrier to prevent accidental piercing of the VIP enclosure by the mechanical fasteners.
Durability and performance checks
VIPs must maintain their properties over time. ACERMI certifcation provides thorough and expert assessment of panels and the quality control system used at the factory. It reliably ensures their performance levels and durability.
The ACERMI Springboard (Tremplin) standard specifcally for VIPs was developed in 2015. It prescribes the methods used to characterize the intrinsic performance of products, for example, thermal conductivity and resistance to water vapor transmission. It also specifes the conditions under which aging tests are performed to assess VIP durability, depending on the intended use (internal or external wall insulation). Six-month accelerated aging tests are carried out under appropriate temperature and humidity conditions. In addition, the standard sets out procedures for assessing the impact of thermal bridges at the edges on overall thermal resistance.