Efflorescence in new Grout.

[MPE]

Just tiled a hallway and used Dark Grey grout which developed horrendous patchy efflorvescence. Any ideas? I contacted the manufacturer NX adhesives, but no reply.

 

[SeanTiler]

pics ?

 

[Bond]

Efflorescence should not be a significant factor in Modern cement based grouts, What type of substrate have you tiled over and any pictures showing the extent of the problem.

 

[Dave]

Sounds more like polymer residue from washing off. Pics would help.

 

[MPE]

pics ?

[automerge]1602529087[/automerge]

Efflorescence should not be a significant factor in Modern cement based grouts, What type of substrate have you tiled over and any pictures showing the extent of the problem.

[automerge]1602529219[/automerge]
The substrate was concrete floor in a hallway that had been down for 30 years.
[automerge]1602529313[/automerge]
It was done in a very hardwater area though that suffers from limescale a lot.

 

[Bond]

Difficult to tell from the picture, efflorescence normally forms crystal like structures from moisture that has evaporated from the surface. May well be lime bloom as you say it’s a hard water area. In any case you should be able to obtain a chemical product to deal with it.