Fast Flex fixings can be used to fix battens, skirting, dado rails or door frames on to aircrete blocks. They may be painted directly without fear of staining.
Fast Flex are also to be recommended when fixing through insulation materials. They offer a 'stand-off' fixing that will not crush the insulant even if they are over hit; and being stainless steel they may be used externally at will offering a good method of increasing thermal insulation on solid walls.
Battens for vertical tiling may be fixed either directly to the bricks/blocks or through the insulation material.
Generally the batten thickness will need to be a minimum of 25mm, although 19mm can be used in special circumstances. This not only ensures a good 'pull-through' value at the batten/fixing connection, but also allows an 'improved' nail to be used to additionally fix into the batten.
The fixing embedment into the brick, block or concrete will depend on the strength of the material, the wind loading and the weight to be supported. As a rule of thumb, concrete requires 30mm, brick 50-70mm and aircrete 70mm+. Reference should be made to Information Sheets TBF1 & TBF2, and the use of a load test unit should be considered.