Bricks and Blocks
There are thousands of bricks to choose from, in a wide variety of colours and surface finishes, and offering many different performance characteristics for different applications. In the main, however, bricks are a standard size of 215mm long * 102.5mm wide * 65mm high. These sizes have not been arrived at randomly but are carefully designed so that bricks coordinate together with an in-built allowance for a 10mm mortar joint, allowing them to be bonded in a walling situation.
Fig. 26 Co-ordinating sizes of bricks with an allowance of 10mm for mortar joints.