World War II
London Brick were initially given orders by the Government to supply bricks for airfield buildings and shelters. Just prior to the outbreak of war LBC had actually produced a book of designs for air-raid shelters, having tested them out at Stewartby.

As the War progressed demand fluctuated. Initially demand increased but deliveries of bricks were hampered by the restriction on transport. Women were employed, as they had been during World War I, for brick pressing because of shortage of labour.

LBC helped with the war effort whenever it could. The engineering works helped with parts for Sten guns. Tanks from America were taken to Stewartby for finishing. The main Bedford to Ampthill road had additional surfacing laid to enable the tanks to be tested. Two of LBC's drivers were trained to drive them. Many of the companies vehicles were surrendered for the war effort as well.