Crack stitching with helical bars delivers an effective and durable masonry repair by introducing into the wall fully concealed tension straps, which strengthen fractured masonry and brickwork.
A series of high-tensile, stainless steel, helical bars are inserted into slots cut into the bed joints and extend 500mm either side, across the crack. The bars stitch or strap the masonry either side of the crack back together and are bonded into the wall using a polymer modified, thixotropic, cementitious grout that does not shrink. Due to the high fin profile and deep continuous deep trough helix the bar forms an excellent bond with the grout. The crack is also deeply filled with grout to restore its strength and to weatherproof the masonry.
Cracks occur in buildings due to movement of one form or another and therefore, crack stitching is often used in conjunction with other methods of structural repair such as lateral restraint and reconnecting perpendicular walls.