Perfect Barrier
Perfect barriers stop all water penetration at a single plane. Such perfect control requires the use of modern materials such as metal and glass. Insulated metal panels can be considered perfect barriers, however, the panel joinery is key to the systems performance as a perfect barrier. The joints between perfect barrier elements may be also designed as perfect barriers (e.g. a single line of caulking or gasketing). The joints can be designed as screened/drained assemblies to manage water at the panel joints (two-stage joints). It is strongly recommended that all joints in prefabricated panel systems and windows should be drained and vented this is often called a rainscreen.Building Science Corporation.

Kingspan insulated panel systems provide for a perfect weather barrier.

• Kingspan panel joints are designed with an overlap nosing that deflects rainwater, protects and conceals the panel fastener.
• Designed to the rainscreen principle, the pressure equalization chamber behind the nosing acts as a second line of defense intercepting and draining water effectively back to the exterior. The balancing of positive air pressure outside with air pressure in the equalization chamber prevents rain water from reaching the sealant
in the panel joint.
• Kingspan panels are designed with double tongue and groove joints allowing for Application of a continuous butyl sealant on the warm side groove provides for air, vapour and moisture resistance (mandatory). Application of a butyl sealant to the outer side groove provides an additional weather barrier (best practice).