Grout color changeing

[Mario]

Never happened this to me before but recently done a job.i used mapei grout beige color and after it dryed looked a bit diferent color in places like it was wet and not dry.left it even after a week and still the same.used clean water clean sponge everything done right.also scraped the area and grout again and now is right.
Any ideeas why did that happen?

 

[Blunt Tool]

If you speak to Mapei about it which a few of us have they will tell you to lightly sand joints, marbling blamed on water content when washing off they say!

 

[Dumbo]

If you speak to Mapei about it which a few of us have they will tell you to lightly sand joints, marbling blamed on water content when washing off they say!

I'm not disagreeing with you but it shouldn't be that easy to mess up . Definitely something Mapei could improve on .

 

[Qwerty]

It's efflouescence. Its caused by over wetting the grout which in turn brings polymers, minerals and salts to the surface.

 

[Dumbo]

It's efflouescence. Its caused by over wetting the grout which in turn brings polymers, minerals and salts to the surface.

Yes but Mapei is one of the most susceptible to this . Also shouldn't be efflouescence as i believe they don't use Portland cement and claim to be efflouescence free

 

[Qwerty]

Efflourescence free if directions followed perfectly. Mapei is a great grout and still one of my favourites but efflourescence still occurs if over wetted. There has been occasions of patchy colour through not shaking bag or incorrect mixing too

@Mapei UK Marketing can help hopefully

 

[Mario]

Basicly was from the same mixing bucket as the rest.but only few grout lines were a bit diferent (wet look).
There were ceramic tile verry high absortion i noticed wen grout and cleaned.wonder if the case of that as well.

 

[Flintstone]

Stick to grout 3000!

 

[Dumbo]

Stick to grout 3000!

I would certainly try it if somebody stocked it in my town

 

[Mapei UK Marketing]

Never happened this to me before but recently done a job.i used mapei grout beige color and after it dryed looked a bit diferent color in places like it was wet and not dry.left it even after a week and still the same.used clean water clean sponge everything done right.also scraped the area and grout again and now is right.
Any ideeas why did that happen?

Hi Mario, all,

With regards to Efflorescence - this is the migration of salts to the surface of the grout, which when the water evaporates leaves a whitish bloom.

Mapei Ultracolor Plus cannot itself produce this because we do not use Portland cement which can release the salts. This is not to say that this can never occur as Portland cement can be found in the adhesive or substrate but as before it cannot come from Ultracolor Plus grout.

The shade variation can be due to a polymer found at the surface which can be attributed to excess water, method or tooling of the joints. The higher the polymer content in the grout the higher the flexibility and water resistance. This can be removed by lightly rubbing with a fine sandpaper.

I hope that this helps! If you have any other queries, please do call Mapei's Technical Service Deparment 0121 5086970 (option 2), open 7am - 7pm week days

Kind regards,
Mapei UK Marketing