These should be laid by an expert in this field. If it is DIY or Owner builder constructed, then you must read and follow the specifications closely. The blocks should not be laid on the ground or directly on to concrete foundations.  A damp proof course should be laid over the foundations and then fix the blocks. Any water absorbed from the ground or concrete will destroy the block or panel. Refer to the specification sheets for further details. The popularity of this form of construction has increased in recent years, due to a lower cost than full brick, and it is a quicker building process.