Grey Mapei grout gone patchy

[DukeofYork]

Hi
We recently tiled our kitchen floor with porcelain tiles. We used Mapei ultracolour grout which is supposed to be dark grey but has dried with large white patches?
Can anyone help? It looks horrendous and our new kitchen is due to be fitted in less than a fortnight
Thanks

 

[John Benton]

Morning Duke you may want to follow this very recent thread

http://www.tilersforums.com/tile-ad...ation/56862-patchy-mapei-grout-any-ideas.html

 

[DukeofYork]

Fantastic thank you! Sorry am new to the site so didnt know how to find old threads

 

[John Benton]

Did you do the tiling yourself?

 

[DukeofYork]

Yes (well my partner and his dad did)

 

[John Benton]

The ratios of grout to water have to be spot on, and with a darker grout is not to have too wetter sponge when cleaning down.

 

[DHTiling]

New threads on same subject are always welcome as each job has it's own take..

I didn't see the other thread... but a number of things contribute to what you have.

This can be over wetting of the grout when washing off and also washing off to soon before allowing the grout to set up... if you leave dirty water in the grout lines that contain polymers from the grout then this will dry lighter...

A remedy for what you have is to clean the joints with a cement residue remover that will also remove polymers.. then follow the directions and clean the joints aided with a scotch pad.. this should bring the joints back up.. but and this is a but!.. this depends if the grout was mixed properly to get an even pigment distribution..

have a read of this as well... http://www.tilersforums.com/tile-ad...on/25037-mapei-ultra-colour-plus-how-use.html

 

[DukeofYork]

Thanks. Think they were spot on with the measurements. Suspect it is related to the cleaning

Any ideas on how to rectify it other than a regrout?

 

[Gazzer]

try a grout colourant

 

[DukeofYork]

Great thank you

 

[Gazzer]

I think it gave good results and saved a lot of time.

PS the original grout wasnt Mapei and damage was caused by flooding.

 

[DukeofYork]

What brand of grout colourant would you recommend?

This is how it looks. It's supposed to be dark grey (I think off the top of my head we got Medium Grey 112) but its nowhere near the sample

 

[Gazzer]

I would use Universeal, click the link Tradetiler Universeal Grout Colour