Unsure

[saintydad]

Just had a workmate call for advice, As I was a tiler many moons ago. His query was one that I couldn't help him with,so I said I would ask the professionals. He had a concrete floor in his brand new house tiled before the 6th of December (about 7 weeks ago) and has told me that the grout is all different colours, He was told that it was still drying out due to the salt in the concrete??? but would dry the same. I felt the length was a bit excessive but as I said been out the game many years now. So please is this a get out or is it possible .Thanks in advance of any advice.

 

[Gazzer]

Was the concrete floor dry ? was it concrete or Screed.
What grout was used ?

 

[Andy Allen]

over wetting the grout when washing it off is one of the most common causes for patchy colour grout...

 

[Qwerty]

over wetting the grout when washing it off is one of the most common causes for patchy colour grout...

Agreed, efflorescence it could well be.

 

[widler]

Sounds like concrete/screed was not dry and is coming through the grout making it patchy

 

[Colour Republic]

My money would be over wetting the grout whilst washing it off. If it is still drying out, then it shouldn't be! Either way, if it was done 7 weeks ago it isn't suddenly going to rectify itself

 

[Andy Allen]

you could use this

to re-colour the grout....comes in different colours..

 

[Peter]

Sounds like polymer leaching if the patchy bits are white-ish.

 

[One Day]

Sounds like it could be UCP to me. Beige perhaps?

 

[Colour Republic]

Sounds like it could be UCP to me. Beige perhaps?

Is that similar to ID Ten T failure?

 

[saintydad]

Was the concrete floor dry ? was it concrete or Screed.
What grout was used ?

Thanks for the reply.The concrete floor was in a brand new Home,wouldnt think they would be allowed to move in if the floors were wet.(But who knows)

 

[Gazzer]

Then as others have said , either over wetting of grout or polymer leaching.

 

[AliGage]

over wetting with some of the quick drying grouts on the market these days seem to be a common problem. i find doing your first wash down with a soft emulsifying pad ensures not too much water is used and that that is gets used to dilute grout residue. not had any issues mentioned above with this method.

 

[Ajax123]

7 weeks is not long enough for a concrete floor to dry thoroughly so it could just be substrate moisture coming through

 

[Gazzer]

7 weeks is not long enough for a concrete floor to dry thoroughly so it could just be substrate moisture coming through

I think you may find it was the tiing that was done 7 weeks ago Alan