Granfix grouting problems

[bizzyboy]

Just used Granfix Jasmin for grouting - some of the grouting is now darker than other areas. Grouting completed a week ago. If I splash water on the tiles, the grouting goes dark and eventually will go light again. Has anyone got any idea why this is happening?

 

[Ian]

If it's left to dry out, does it all go a consistent colour? Or is it still patchy when dry?

 

[bizzyboy]

Thanks for your response. I have patches here and there of a darker grout. It was grouted nearly a week ago so grout should be dry I think by now.

The other problem is, if I spray the wall tiles with the bath shower hose , the grouting goes a dark colour from the water - I did this last night but this morning the grout is a normal colour.

 

[Ken Bruty]

It's normal for grout to go darker when it's wet and then light when it's dry because it is absorbent. However if it's patchy when it's completely bone dry, then it was probably overwashed when applied or applied onto a surface that was too damp, this causes the pigment loss that you will see when it is bone dry. If it is crumbly in certain areas, it usually shows bad mixing or over watering it when mixing it initially and applying it too wet, in which case it would be advisable to scrape it out and get it re-grouted paying very close attention to the manufacturers mixing quantities and then wipe it of with a damp sponge rather than a wet one. Hope that helps

 

[bizzyboy]

Thanks Ken for yr feedback - much appreciated . Have never had the problem of the grout changing to a darker colour when wet in my other bathroom with a shower so this was unexpected. In the other bathroom the grout always stays the same colour (cream) whether it is wet or not. Would applying a sealant to the grouting help keep the colour - tiles are ceramic. Grouting doesn't appear to be crumbly.

 

[Ken Bruty]

Sealer can help, yes, but you may have to go over it a few times, it just depends how thorough you are. Put one coat on and see how you go, if you see any dark spots when it gets wet, mark where it is let it get completely dry and apply sealer to that bit and so on, for the future, epoxy grout is water repellant and doesn't change colour in my experience of it, but hard to apply for a rookie unless you are very methodical and well practiced and don't mind sweating a bit, and it's also very expensive but you do get a fantastic finish with it

 

[bizzyboy]

Thanks Ken. I plan to get a sealant and have had Lithofin Grout protector recommended to me - is this a good make to use or do you suggest something else? We follow through what you suggest.

 

[Dan]

Welcome aboard. Hope you find the tilers forum helpful.