Allocation for the wind uplift protection system

Calculating the wind uplift resistance

What is a wind uplift protection system?
A wind uplift protection system is required to withstand wind loads and counteract wind uplift.
A wind uplift protection system is the interaction of three individual components.

Substructure, e.g. timber battens or metal construction,
Roofing material, e.g. clay tiles, concrete tiles or natural slate,
and mechanical fixings e.g. a storm clip.

What does an allocation mean?
An allocation is made by considering the three individual components of the wind uplift protection system, i.e. batten size, covering material and storm clip.

This combination is evaluated in a system test according to the current standard EN 14437. FOS system test

The result of the test is the wind uplift resistance of the fixed roof covering. In the wind load calculation for a building, the wind uplift resistance must be at least equal to or higher than the wind load on the object.

What is the DIN EN 14437 test seal?

The European standard DIN EN 14437 specifies test methods for determining the lift-off resistance of roofing materials that lie loosely or are mechanically fastened to the substructure. The determined resistance values of the stapled covering apply in each case only to the tested staple-tile-batten combination. FOS® carries out the required test procedures on the test stands in the application technology and feeds the values into the FOS WindCHECK®.

How can you calculate the wind load for your building and covering material quickly and easily?
You can use our wind uplift calculation tool FOS WindCHECK® to determine the allocation of storm clips with sufficiently high wind-uplift resistance specifically for a batten, a covering material and a building located in Germany and Austria The wind uplift calculation is carried out for Germany according to the current trade regulation and for Austria according to the Ö-Normen EN 1991-1-4 and B 3419. As a result you will receive not only the type and number of clips but also the laying patterns showing the positions of the clips.

What must be considered when making allocations?
A clip of the same design can be used on diﬀerent roof tiles, but the wind uplift resistance must be determined with a separate system test for each tile type. Allocations and laying patterns cannot and must not be transferred to other objects, storm clips, covering materials or different batten thicknesses.

The test procedures for the allocations are carried out by FOS with timber battens and roof tiles on our specifically designed test facilities. Tolerance deviations with any of the three components cannot be taken into account. Test reports with the results are issued and FOS is able to provide these on request. This ensures that FOS® storm clips meet the requirements of the current german trade standards.

The conformity of the storm clip, verified by the system test, means that an additional building code approval is not necessary in Germany. Storm clips are listed under part C in the German building rules list.