Grout Efflorescence problem on black grout

[Craig Blick]

Hi, I've recently laid 600x300 quartz starlight in our bathroom, used flexible black grout for joints, they've almost turned white/ light grey. Ive read i can use lithofin cement away or similiar products to take the efflorescence aeay and restore the grout to the black colour its supposed to be...would this product be suitable for quartz or would it cause some damage?

 

[Dumbo]

I think it will damage the tiles as I've had this with supposed granite tiles @Lithofin BOB is the best qualified person to speak to on this

 

[Craig Blick]

I think it will damage the tiles as I've had this with supposed granite tiles @Lithofin BOB is the best qualified person to speak to on this

Cheers thanks for reply

 

[J Sid]

don't believe you can use it but that really relevant because if you black grout has gone light grey or white even an act of god will not get them back to black, worrying

 

[Craig Blick]

don't believe you can use it but that really relevant because if you black grout has gone light grey or white even an act of god will not get them back to black, worrying

Thing is i tried the olive oil trick on a small area and it worked but obviously not a permanent solution, also when wet it goes back to black, ive been advised by my local tile warehouse that their cement away product is suitable for quartz but im dubious...unless i could get it in writing from them and then if it does cause damage they are liable?

 

[Dumbo]

Time today go to boots and get whatever girls use for doing their eyebrows . That should get it back to black .

 

[Craig Blick]

Time today go to boots and get whatever girls use for doing their eyebrows . That should get it back to black .

And then wash off with the next mop lol

 

[hmtiling]

I think it will damage the tiles as I've had this with supposed granite tiles @Lithofin BOB is the best qualified person to speak to on this

Was it basalt sold as granite?

 

[Dumbo]

I think it was granite chips bound up together with resin and I think that the acid bleached the resin . When I contacted the manufacturer about it they weren't very helpfull . But when I told them no way no how will this product damage pure granite they sent me need tiles and paid me too relay the floor .

 

[Dumbo]

Time today go to boots and get whatever girls use for doing their eyebrows . That should get it back to black .

Mind you that would only be good for ten mm grout joints

 

[Lithofin BOB]

Please Do not use cement away , this is an exterior only product -hydrochloric acid will cause you much more problems than grey black grout. I would stay away from anything acidic, as This can also whiten the resin in an aglomerate tile. You could test a light alkaline product , we have power clean ( others makes avalible ) and a white pad , as Julian , you will be lucky to get this back. Have you had a test scrape, is the black colour under the surface, if not - cleaning won't help here.
Could you use a grout revival product on it, other than rake it out

 

[J K Tiling Cornwall]

Hi Craig,
Efflorescence on the surface of the grout
Joints can be more of a problem with non porous tiles as adhesives and grout have longer drying times. I think the tiles you mention may be a composite (Stone resin) did they have a fibre glass resin smell when cut on the wetsaw? Have had before and it does clear with time and wiping down (the adhesive may still not be fully cured) would avoid any acids or strong chemicals just yet, would advise testing on a off cut first. As a last resort Mapei do a colourant, but have not used myself. Hope this helps.
James.

 

[Craig Blick]

Hi Craig,
Efflorescence on the surface of the grout
Joints can be more of a problem with non porous tiles as adhesives and grout have longer drying times. I think the tiles you mention may be a composite (Stone resin) did they have a fibre glass resin smell when cut on the wetsaw? Have had before and it does clear with time and wiping down (the adhesive may still not be fully cured) would avoid any acids or strong chemicals just yet, would advise testing on a off cut first. As a last resort Mapei do a colourant, but have not used myself. Hope this helps.
James.

Thanks for reply james I'll give the colourant a go as rather not ruin tiles, yeah they did have that kind of resin smell when cut do ill avoid acid for now cheers

 

[Craig Blick]

Please Do not use cement away , this is an exterior only product -hydrochloric acid will cause you much more problems than grey black grout. I would stay away from anything acidic, as This can also whiten the resin in an aglomerate tile. You could test a light alkaline product , we have power clean ( others makes avalible ) and a white pad , as Julian , you will be lucky to get this back. Have you had a test scrape, is the black colour under the surface, if not - cleaning won't help here.
Could you use a grout revival product on it, other than rake it out

Hi could you recommend the best product you offer for this problem? Cheers

 

[Dumbo]

Hi could you recommend the best product you offer for this problem? Cheers

He did . Power clean

 

[Lithofin BOB]

As James, test your cleaner on an off cut, did you have a test small scrape at the surface to see if the original colour is there.