Grout cracked, deteriorating or falling out

Cause

Moisture in grout 

Repair

  • if the problem is just with the grout between the tiles and not the tiles themselves, rake out the existing grout. Clean the joints thoroughly and then re-grout. Only use a product specifically designed for the purpose and situation and follow the grout manufacturer’s instructions
  • epoxy grouts are an option for the grouting. They are usually more expensive, but are non-absorbent, colourfast and more permanent and unlikely to support mould. They must not be used where a flexible joint is required, so do not use over a construction joint or at wall/floor junctions or wall/wall junctions – use a flexible sealant here instead
  • in the Building Code, Acceptable Solution E3/AS1 requires that tiles in wet areas have 6% maximum water absorption, waterproof grouted joints and be bedded with an adhesive specified by the tile manufacturer as being suitable for the tiles, substrate material and the environment of use

Cause

Substrate movement

Repair

  • if the substrate and the tiling were installed in recent years, call back the tradespeople who did the work
  • tile manufacturers typically require that expansion or movement joints for floors and walls be carried through both the tiles and bedding material
  • it is good practice for the edge sealant to be flexible to allow for movement (a) around the perimeter where the tiles abut a rigid element, (b) where there are movement control joints in the substrate, (c) within the body of the tiled area, and (d) where two tiled surfaces meet such as an internal corner or a floor/wall junction

MMH Substrate Movement Repair2

Cause

Grout not firmly bedded into joint when laid

Repair

  • if the tiles were installed in recent years, call back the tradespeople who did the work
  • if the problem is just with the grout between the tiles and not the tiles themselves, rake out existing grout. Clean the joints thoroughly and then re-grout. Only use a product specifically designed for the purpose and follow the manufacturer’s instruction
  • use a flexible silicone sealant at wall/floor junctions and include movement control joints as described in the repair above

Cause

Lack of movement control joints

Repair

  • if the tiles were installed in recent years, call back the tradespeople who did the work
  • tile manufacturers typically require that expansion or movement joints for floors and walls be carried through both the tiles and bedding material
  • use a flexible silicone sealant at wall/floor junctions and include movement control joints as described in the second repair above