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Bathroom Fitting

Is silicone required over grout?

We've had a wet room for a number of years now but we're finding that the silicone over the grout at the edge of the floor requires replacing around every year.
The tiles are almost slate like in texture, rough to the touch so are likely porous. There's a decent bead of grout between the wall and the floor tiles, and there's been a further decent bead of silicone over that. We've found at black mould tends to gather between the silicone and the grout, but doesn't appear to affect the grout, it's simply sticking to the silicone.
So my question is, is the silicone required on top of the grout or are we asking for trouble by leaving it off?
Any help greatly appreciated. We're now quite sick of the annual scrape and replace.

3 Answers from MyBuilder Bathroom Fitters

Best Answer

Ideally you need the silicone to complete the water barrier around the room
It sounds like the current silicone is not a true sanitary silicone, which WILL HAVE anti fungicide mixed into it the tube will state if anti fungal protection is there.
Make sure that when you scrape off the current silicone you use a chemical silicone remover as this will remove all current silicone and kill any fungicide. Make sure the area is totally dry before applying new silicone this will give the best results for longevity


Answered 7th Sep 2012


For the best result remove the grout from the edges than you can apply your sealant. This way the sealant can go into the gap between the floor and wall tiles which should not be more than 2-3mm. Make sure the surface is clean and completely dry. It should be ok for 5 years if you keep it clean.



Answered 7th Sep 2012

forever white or bal silicone, best products available


Answered 9th Dec 2012

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