Crack repair products strengthen cracked masonry walls by enhancing the tensile, flexural and shear strength of brickwork using various brick reinforcement techniques. Sealing fissures with appropriate fillers help to restore compressive strength and protect against water infiltration and frost damage.
Cracks are usually the result of the structural movement of part of a building. The displacement may be historic, cyclic or on-going. Predictably, a masonry structure can move when it exposed to the effects of variations in temperature, chemical reactions, age deterioration, vibration or changes in the moisture content of brickwork, or the ground that supports it. Once a wall fractures, it is no longer a composite structural unit.
Typical defects that may trigger cracks include any one or a combination of:
Ground movement – Subsidence, land slip or heave
Inadequate support – Localised foundation failure, lintel failure, masonry arch failure, etc.
Insufficient restraint – Lack of wall ties, restraint straps, poor bonding, etc.
Resizing – Expansion or shrinkage due to thermal or moisture variations
Rusting metals – Wall tie corrosion, expansion of hoop irons or fixings, etc.
Identifying and eliminating the cause of the fracturing is essential in ensuring the lasting success of a masonry repair scheme.
Generally crack repair strategies fall into one of two categories:
Sub-structure repairs for below ground foundation movement issues, typically an insured risk
Superstructure reinforcement for above ground building defects, typically an uninsured risk
Sub-structure repairs may include underpinning or piling.
Superstructure reinforcement generally includes structural repairs accomplished by the insertion of helical bars that form retrofitted brick beams or crack stitching systems Replacement wall ties and restraints tie cavity walls or separating façades, whilst resin injection products efficiently fill and seal cracks in walls
After resolving the source of faults or weakness, fill the cracks and reinforce the zone of brickwork that has fractured to ensure once again it performs like an integrated structural unit. Crack repair techniques include mechanical brick stitching and crack injection resins, whilst various tie and strapping systems help to constrain further movement by transferring and sharing loads.
* 10 BAR KIT* Professional crack stitching kit with everything needed to improve the structural performance of cracked brickwork and stone walls. Contains 1m x 6mm helical bars, offering high tensile stainless steel reinforcement.
Crack Sealer Plus is a pure injection filler designed to bond those hard to fill narrow cracks in bricks, blocks, render and concrete. Small flexible nozzles enables masonry cracks as fine 2mm wide to be filled and sealed.