Systems Building Maintenance
Building Maintenance 'done right the first time'

Crack Stitching

Repair and Reinforce.

What is Crack Stitching?

Crack stitching is the repair and reinforcement of damaged masonry which addresses the problem by re-establishing structural integrity.   

In conjunction with Thorhelical, Systems Building Maintenance can repair even the most traumatised masonry.   

Systems Building Maintenance chooses Thorhelical’s products and methods because of their excellent quality, comprehensive range, technical expertise and proven track record over the past 25 years.   

Thorhelical’s product range includes stainless steel remedial wall ties, fixings and structural reinforcement bars, providing strength, durability and holding power to damaged masonry walls, while allowing flexibility.  

All products and methods have been exhaustively tested by accredited independent authorities, while remaining cost-effective.

Benefits of Crack Stitching

Anchored across fractures the grouted helical crack repair ties generate excellent compressive and axial strength to reinstate the structural integrity of distressed masonry to its pre-cracked strength and to provide resilience against further cracking.

Under axial loads the crack stitch tie becomes stressed within the wall. This torsional build up enables the spiral bar to progressively accumulate load & to disperse it at tangential angles to its helix along the full length of the reinforced zone to fully reinstate the structural integrity of distressed masonry and provide resilience against further cracking.

The redistribution of stress along the rods full length alleviates the incidence of sudden and catastrophic failures.


  • Chase 10mm slots at 340mm intervals, (every 4 courses), along a length of wall that extends 500mm each side of crack. Depth of slot – refer to table with allowances made for any render/plaster finish.
  • Clear loose detritus from slots ensuring exposed brick surfaces are cleaned of mortar and flush thoroughly with water, or treated with a suitable primer.
  • Pump bead of Thor Helical D.U Grout to rear of slot, filling it evenly to approximately two thirds full.
  • Push Thor Helical 6mm crack stitching tie into grout to approximately two thirds of slot depth. Trowel displaced grout to firmly encapsulate rod.
  • Make good wall chase to disguise slot. Repair cracks between the helically reinforced masonry with appropriate and discreet filler.