Rapid lay building bricks

Claim 1

A rectangular prismatic building brick having two planar end faces, two side faces and an upper and a lower face, at least one vertical groove formed in one side face of the brick positioned so as to divide the side face into parts of equal length and shaped to simulate a vertical brickwork joint and a rib extending outwardly from one of said planar end faces of the brick a distance substantially equal to the width of said groove and substantially across the said one end face, and a surface on the said first rib set back from the said one side face by a distance equal to the depth of said groove whereby the said surface is adapted to form a groove bottom between two adjacent bricks in a wall structure, the depth of the rib measured from the said surface being substantially less than the width of the said end face whereby the said rib serves to space the said end face from an adjacent brick to form a gap therebetween for mortar, further comprising a second rib extending outwardly from the other side face of the brick a distance equal to the width of the groove and substantially across the said other side face and a surface on the said second rib set back from the other end face of the brick by a distance equal to the depth of the said groove, the depth of the rib, measured from the said other end face of the brick being substantially less than the width of the said other end face of the brick whereby the said rib serves to space the said other side face of the brick from an adjacent brick at a corner of a wall structure to form a gap therebetween for mortar or the like, the brick being surrounded on the normally vertical end faces and side faces by a jacket of plastics material, the plastics jacket at the end faces being perforated so as to bond with mortar.