How to fix porous grout on shower floor?

sandytat2012

Hi there, I added a layer of less porous grout (Dunlop Ready To Go Colour grout) on top of more porous grout (original from builder).

The issue is as I couldn't do this to the original grout area right underneath the shower screen, hence now I may have a problem that as water go from the area right underneath the shower screen (which still have original more porous grout) and sweep through sideway to other area where I have old more porous grout underneath with a layer of less porous grout above, that may lead to water and moisture trap underneath?

I looked at the Dunlop Ready To Go Colour grout is cement based, so I assume eventually the water will evaporate but just slower? Would this pose a problem short term and/or long term? Any advice would be much appreciated!!

You can see from below photo -

> the red circle show the corner area where I didn't add new grout, and it's still wet/damp

> the blue circle is the area where I also couldn't add new grout as it was right underneath the shower screen

MitchellMc

Welcome to the Bunnings Workshop community @sandytat2012. It's wonderful to have you join us, and many thanks for your question about grout.

All grout is porous and allows a small amount of water through. However, the red circled section looks to have grout that is lower than the surface of the tiles. The grout needs to finish flush with the surface of the tiles so water can't sit in it. You've done a good job where you've applied it. Make sure you scrub it off the surface of the tile before it sets entirely. I would suggest adding grout to the area circled in red.

Are you trying to address water that is creeping under the shower screen? If so, there should be a water-stop under the screen that prevents water from escaping. You might like to run a bead of black silicone between the shower screen and your tile, the area you've circled in blue. This should help stop water from escaping.

Please let me know if you have any questions.

Mitchell