The structural integrity of a penetration-free mounting system is achieved by the dead weight, module weight and additional ballast. Prerequisites for a proper assembly include suitable roof construction, as well as sufficient loadbearing reserves of the building.

A significance influence on the structural integrity of this type of construction is the interaction between roof covering and the building protection mat, and between mounting system and building protection mat, which are defined by the coefficient of friction. The coefficient of friction is incorporated in the static calculation 1:1. It is therefore necessary to determine the friction coefficients on site and verify them.

• Prepare the roof surface for subsequent assembly and if necessary clean with water
• Place the test weight on the roof surface and leave for 10 seconds
• Pull the spring tension balance at a right angle to the roof pitch
• Read the weight as soon as the test weight starts to slide
• Measure on dry and wet roof surfaces at several locations
• Measure the high and low points, the corner, edge and center area of the surface.