Masonry

Control Joints

BoMetals masonry control joints are available in both PVC and Rubber compounds. They are standard black in color in 4′ lengths. Special lengths are available on request.

Masonry Control Joints

Catalog # Material A B C D #lbs./LF
BCJ-1 PVC 2 3/8″ 5/8″ 1 1/2″ 5/16″ .75
BCJ-8  Rubber 2 3/8″ 5/8″ 1 1/2″ 5/16″ .52
BCJ-2 PVC 2 3/8″ 5/8″ 1″ 5/16″ .60
BCJ-9  Rubber 2 3/8″ 5/8″ 1″ 5/16″ .42
BCJ-3 PVC 6 3/8″ 5/8″ 1 1/2″ 7/16″ 1.00
BCJ-10  Rubber 6 3/8″ 5/8″ 1 1/2″ 7/16″ .69
BCJ-4  PVC 10 3/8″ 5/8″ 1 1/2″ 7/16″ 1.35
BCJ-11  Rubber 10 3/8″ 5/8″ 1 1/2″ 7/16″ .94

Cracking in block walls 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.

Spec Sheet

Physical Properties

Properties of PVC Control Joints Test Method of PVC Control Joints Nominal Value of PVC Control Joints
Tensile Strength ASTM D-638 1500 PSI
Elongation ASTM D-638 300%
Specific Gravity ASTM D-792 1.40
Hardiness Shore A ASTM D-2240 85 + /-5
Properties of Rubber Control Joints Test Method of Rubber Control Joints Nominal Value of Rubber Control Joints
Tensile Strength ASTM D-2000 750 PSI
Elongation ASTM D-2000 300%
Hardiness Shore A ASTM D-2000 70 + /-5