Tiling around showers, baths – sign of water leaks

Cause

Leaking in-wall plumbing fittings or pipework 

Repair

  • if the leak is likely to come from building or plumbing work undertaken by a tradesperson relatively recently (within the last couple of years), call them back

  • work on any pipework, fittings or appliances that are connected to a sanitary fixture (which includes a shower) is restricted work and must be carried out by a licensed or certifying plumber. Homeowners cannot make these repairs themselves

  • if the wall lining has become wet it will likely require replacing. The timber wall framing will need to be dried down to a moisture content of 18% before relining can take place. Framing would also need to be checked for signs of decay. If there is any indication of decay, a prudent approach would be to engage an experienced building surveyor to make an assessment

  • the licensed practitioner making the repairs should contact the building consent authority (BCA) to see whether they require building consent or an inspection. It would be prudent to involve the BCA to check the moisture content, and to look for waterproofing certification from a licensed applicator

  • if the shower or bath back on to another room, check in that room for signs of dampness, water stains and/or mould

Cause

No waterproof membrane behind the tiles 

Repair

  • in almost all cases, tiles in wet areas must have a waterproof membrane behind them. If the tiling work was carried out by tradespeople relatively recently (within the last few years), call them back

  • the only long-term solution is to take off the tiles, apply a waterproofing membrane to the required area and then reapply the tiles. You can find guidance in the Building Code Acceptable Solution E3/AS2 Internal wet area membrane systems. This document references a Code of Practice for Internal Wet-area membrane systems. These documents can be downloaded from the Internet at no cost

  • you can also find information on the BRANZ Level website

  • the substrate should not be damp when the waterproof membrane is applied. Concrete slabs should have a relative humidity no greater than 75% and plywood should have a moisture content no higher than 18%

  • if the wall lining has become wet it will likely require replacing. The timber wall framing will need to be dried down to a moisture content of 18% before relining can take place. Framing would also need to be checked for signs of decay. If there is any indication of decay, a prudent approach would be to engage an experienced building surveyor to make an assessment

  • the licensed practitioner making the repairs should contact the building consent authority (BCA) to see whether they require building consent or an inspection. It would be prudent to involve the BCA to check the moisture content, and to look for waterproofing certification from a licensed applicator

  • if the shower or bath back on to another room, check in a that room for signs of dampness, water stains and/or mould

Cause

Damaged tiles or grout

Repair

  • as above