ABSTRACT
This chapter deals with ties commonly used in cavity wall construction and describes the more sophisticated techniques for supporting and restraining brickwork cladding to framed buildings. The designer will determine the distance between ties to give the required strength and possibly to suit the placing of thermal insulation batts or boards. Steel straps are used to tie the inner leaf of blockwork of a gable wall to the roof trusses or rafters to prevent the gable wall from being displaced by the wind. Bricklayers are responsible for building-in damp-proof courses, including cavity trays, to prevent the penetration of rainwater and ground moisture. Vertical movement joints allow brick walls to move horizontally along their length, but it is necessary to prevent the ends of the leaves on both sides of a movement joint from moving at right angles to their length. Bricks are supported on individual brackets which have stiffeners which fit into the vertical cross joints.
