fixing grout gaps in shower cubicle

[Mirjam]

Hi there!

A friend has a shower cubicle where there are a couple of little gaps (5-10 mm) in the grout. Doesn't look like it has fallen out but like it was sloppy grouted to start with. The shower has been used for several years. Do you think there is water damage behind the tiles now? Is is ok to fill those holes with some grout or will that just trap the moisture?

grateful for advice

 

[White Room]

What was the preparation before it was tiled, tanked etc

 

[Mirjam]

Have no idea how it was prepared and tiled. The shower is in Austria. Everything looks professionally tiled otherwise and it is a nice flat well refurbished otherwise so I can't imagine no tanking has been used but don't know. There are no signs of water damage or loose tiles, just the little gaps which are located low down on the walls where all the water splashes.

 

[White Room]

Whatever you put in the gaps it will show up as you state it was tiled several years ago, I'd be squeezing some good quality Silicon into the gaps but make sure it's dry on the tiles otherwise it won't stay there and if there are signs of leaking at a later date then time to redo.

Could also do a regrout but thats not a quick job.

 

[Mirjam]

Thanks Whitebeam! I'll use Silicon but don't understand what you mean with that "whatever you put in the gaps it will show up". Will the mould show up you mean? I am worried that there is moisture behind and that I trap it by filling the gaps.

 

[White Room]

The old grout maybe discoloured so anything new will be very white, if it is white, against the existing grout.

If your worried about trapping moisture the existing grout should allow a certain amount to evaporate, it all depends how much use the shower gets used and wether there is a power shower throwing gallons of water into the cubicle, say everyday and how many use it.