All tiles absorb water. Just how much water will be absorbed will be determined by the structure of the tiles and the way it was made. Handmade terracotta tiles that are fired at low temperatures generally would have a high absorption rate (perhaps 15%) and porcelain tiles are known to have the lowest (as little as 0.1%).
Whilst the glazed finish on glazed ceramic tiles is impervious to water, if there is a leak or excess moisture, the tile may become wet from behind or underneath. This is often more evident in a harsh, wet environment like a shower recess where wall tiles are often made with a softer biscuit (base).
Because the glazed surface is not unlike a glass finish, if the tile biscuit is wet, the tile will appear darker on the face of the tile.
Simply, water is managing to get behind the wall or under the floor and soak into the tile.
This can be due to a number of reasons including:
• The shower recess was not waterproofed before tiling
• The waterproofing has failed
• There is a leak in the water pipes behind the wall
• The taps are not sealed and waterproofed where they meet the tiles
• The floor is flooding and not draining correctly
• Water is pooling on the floor of the shower and not draining away
• The grout is cracked or falling out
This can be a serious problem and needs to be attended to quickly. The longer that it remains unfixed, the more damage can be done to the substrate and even the structure of the home.
• Call your builder
• Call a plumber to determine is there is a leak in the pipe-work or tapware.
• Call a builder or tiler to repair the grout, silicone joints, or other cause of the leaking water.
• If it is obvious that the problem is due to cracked, missing, or very soft grout and silicone; you may like to repair it yourself, talk to the Ranjanas Ceramic staff about a fact sheet on how to do it.
Regardless of your final solution, install fluid aprons around your taps. These nifty little gadgets are available from
Once the cause is fixed and the tiles are given the opportunity to dry naturally, the dark shading should disappear.
