Silicon or grout for small bathroom job

[Peterhoop]

We have a bath/shower with tiles on the walls around the bath. On the wall side of the bath the wall is partly recessed with a tiled shelf connecting the bath to the wall (photo attached). The tiles on this shelf are cracked near the join with the wall and water is leaking through them. We have a handyman/builder who will replace the tiles on the shelf. He has suggested fixing the replacement tiles at a slight angle to the bath to allow water to run off into the bath. Also, he is suggesting using silicone instead of grout for the tiles. However, I have been told that black mould is likely to form on the silicon. Is this so, and is it better to use silicone or grout, or a combination of both for this job?

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Asked by: peterhoop

 

[PaulSmith]

Would be using a good quality silicone here.

 

[Peterhoop]

Would be using a good quality silicone here.

Thanks for that Paul. And would that be just around the edges where the tiles on the shelf join the wall and the edge of the bath, or between the tiles as well? Currently the tiles on the shelf have grout between them. I assume a silicon with mildew protection would stop mould forming?

 

[PaulSmith]

That'll be silicone where edges meet edges. Grout between the tiles as usual

 

[Peterhoop]

That'll be silicone where edges meet edges. Grout between the tiles as usual

Sorry Paul, I'm not a professional, so excuse my ignorance (I think I may be on the wrong part of the site for the rank amateur). My main concern would be to stop cracks reappearing which I suspect were caused by expansion/contraction of the tiles and maybe movement of the bath.

 

[Rich Midge]

Kind of answered your own question. If the bath is moving or the shelf is moving you're going to be fighting a losing battle. The black mould you see on silicone is generally caused by standing water and soap residues.

 

[Peterhoop]

Kind of answered your own question. If the bath is moving or the shelf is moving you're going to be fighting a losing battle. The black mould you see on silicone is generally caused by standing water and soap residues.

Thanks Rich. But would it be an idea to use silicon (instead of grout) between the tiles on the shelf as well as around the edges to give more flexibility to absorb tensions caused by expansion/contraction of the tiles or movement of the bath? Is that something worth trying or something a professional would never do?

 

[Rich Midge]

As a professional I'd remedy the movement first! But yes, given its such a small area you could try silicone in the joints. Buy the best quality you can, give plenty of time to cure and always rinse and dry after use. Best of luck.

 

[Peterhoop]

Ok Rich. Thanks very much for your help.