AAC blocks provide superior strength that gives resistance against cracks, impact strength and acoustic performance. The blocks can be used in internal and external applications, either as infill or load-bearing walls. Specified manufacturing sizes of blocks allow for 10mm (3/8 in) mortar joints and satisfy the concept of basic size, i.e. the basic scape to be occupied by the block and its share of the joints, in accordance with BS 3626, “Recommendations for System of Tolerances and Fits for Building”.