Point Load Testing

Concentrated load must be applied in a direction perpendicular to the roof through a circular steel disc of 100 mm diameter faced with a 20 mm thick rubber pad, with a Shore A Durometer hardness of 30-70, to the part of the profile judged to be least resistant to load. See Point Load Test at the MRM.

Where the dimension of the sheeting profile does not allow the use of a 100 (±2) mm diameter pad, the shape must be spread over two ribs by way of a disc and pad of 100 mm width.

The pressure cell and deflection sensor are positioned above the profile pan or rib at mid-span. For Type A (unrestricted access) and B roofs (restricted access), the load is increased to 1.32 kN, the pressure is released and residual deflection measured after 1 minute. Residual deflection must be less than S/1000 or 1.5 mm, whichever is higher. The pressure is then increased to failure (or at least 2.41 kN) and noted.

For roofs only intended for Type C (non-trafficable) applications, the initial pressure requirement is 0.60 kN, and secondary load is 1.1 kN.

Point Load Testing: Various Profiles

Point Load Testing on different profiles

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