Masonry Accessories

PVC and Rubber Control Joints PVC Weep Tubes Block Cap

Cracking in buildings normally results from restrained movement. This movement may originate within a building material due to temperature change or shrinkage, or may result from movement of adjacent building elements. In most cases, movement is inevitable and must be accounted for during design if cracking is to be controlled. BoMetals Control joints, when placed in concrete masonry walls, are an excellent method of crack control.

Control joints are vertical separations built into a concrete masonry wall to reduce restraint and permit longitudinal movement. They are located where cracking is likely to occur due to excessive tensile stress.

Control joints are typically located at

wall openings

changes in wall height or thickness

construction joints in foundations, roofs and floors

wall intersections

a distance of not over one-half the allowable joint spacing from all corners

a determined spacing for the length of the wall

For walls without openings, control joints are used to effectively divide a wall into a series of isolated panels.