Black grout on mosaic tiles. Grey patches. How do I fix the colour?

[russy47]

Hi there,

My first post here. I have read a couple of threads on the patchy black grout issues other have had. But not sure what remedy to use to fix my grey patches. Think I need gresian 2000 grey away!

Basically Ive got black mosaic tiles with black grout in the bathroom.
Im no pro tiler but the grout went on ok a couple of years ago when i did the job. Though i may have rushed a little towards the end of it!?!?

Anyway, around the shower where they get the wettest, the grout is fine and the black colour is even. all other areas the grout is patchy in areas. more charcoal grey than black.

Ive read about this aqua mix colourant and enrich and seal. But theres no way im going along hundreds of grout lines with this stuff unless its okay touching the tile surface???

I presume this discolouration has been caused by either effloresence and/or the grout being over wetted when wiping off after grouting??

So, short of applying another grout coat over these dodgy areas, what can i do to get an even black colour.

I liked the olive oil test someone mentioned and had previosuly wondered if such an oil exisited to put onto grout and tiles. Presume thats what the enrich and seal is maybe??

Any help much much appreciated!!

Russ

 

[andersontiling]

it may be our old mate efflorescence.i would try hg blue or remover diluted 7-1 rub the whole area with an emulsifying pad.this should bring the grout back to its natural state.if that doesnt work linseed oil will soaks into the joints and keeps them a uniformed dark color...hope this helps :huh2:

 

[russy47]

thanks for the reply.
the more i read and think about it, the more i think its that I have over wetted when cleaning down.
im thinking the only way to get an even colour is the Aqua Mix grout colorant and then enrich & seal after that.
couple of pics hre showing the difference where the grout is blacker than the tile, and then where it is grey.

I'll ask aqua mix aswell, but will i be ok just brushing colourant on to the grout and wiping off excess from the tiles as i go??
the tiles are a very smooth finish and dont seem porous enough to take up the colourant, but i guess maybe id just have to test?

 

[DHTiling]

Have you used any bleach in those area's..?

 

[russy47]

no not that i remember Dave.
they have looked like this since the grout dried when I originally did the bathroom a couple of years ago.
The main thing i notice is that where the tiles do get wet near the shower, the grout is nice and black, even when completely dry. Its the area that get no water on em that are patchiest.

 

[DHTiling]

was the grout a flexible one..?

 

[russy47]

No. It was a standard Bal Charcoal black grout.

 

[DHTiling]

BAL........well there's your prob....Bal black grout is well known for this problem in the tiling world..

Effloresence....try some lithofin kf cement residue remover.. and if that dosn't restore it then maybe you will have to look at a re-colour...

here's some info on the lithofin product..

Broken Link Removed

 

[russy47]

will have a read now. cheers dave.
though ive almost resigned myself to re-colouring. i get the impression its more than just surface effloresence

 

[LM Ceramics]

i did noticed i used black grout on a bathroom with glazed black ceramic tiles i used keraquick black grout and it also dried abit grey i hate the stuff