Structural Sealant Glazing and Spider Fitting Glazing. Determination of Thickness

The first article, “Traditionally Installed Glazing: Determining Thicknesses” ( [N 4 405] ), addressed glazing installed in frames with glazing beads that meet the requirements of standard NF DTU No. 39, or glazing consisting of a single unit of tempered glass.

This article specifically addresses glazing when it is bonded to a substrate (VEC – bonded exterior glazing) or point-fixed to a structure (VEA – attached exterior glazing).

The rules applicable to these glazing systems are taken from CSTB technical reports No. 3488 for VEC and No. 3574 for VEA, which define, on the one hand, the loads that must be taken into account and, on the other hand, the criteria that must be met depending on the installation technique.

The mechanical performance of glazing depends on the nature of its basic components, the way these components are assembled in the final glazing unit, and the load exerted on the glazing during installation.

We will therefore focus on specifying the loads acting on glazing systems based on their installation type, and then provide the calculation formulas used to determine their thickness.

Calculation examples are provided to illustrate the process for determining the correct composition of a glazing unit.