Mapei white grout absorbing water

[Jacko028]

Hi after some advice . Just finished the shower cubicle , used a Mapei white grout and the grout goes grey and absorbs water . After a while it dries out again , but this is not normal ? I have the same tile in my other bathroom but used a cheap travis Perkins 4 trade grout and had no problems . My builder insisted on using this ( he did the refurb ) a decent quality white adhesive was used Norcros , the wall was prepared with an acrylic primer . Just cannot understand why the grout is absorbing water like this ?

 

[Dave]

Grout will wet up when wet , try using a grout sealer

 

[Jacko028]

I’m worried if I seal the grout it may seal the wet colour in as I will be applying a liquid , and the darker colour ( when it gets wet ) may stay . I’ve not had this problem in my other bathroom with the same tile and white grout ( cheap 4trade one ! ) will never use Mappei again awful product .

 

[Dave]

I’m worried if I seal the grout it may seal the wet colour in as I will be applying a liquid , and the darker colour ( when it gets wet ) may stay . I’ve not had this problem in my other bathroom with the same tile and white grout ( cheap 4trade one ! ) will never use Mappei again awful product .

If the grout is dry , then seal it won’t alter the colour. I sealed mine with lithofin stain stop.

 

[Jacko028]

If the grout is dry , then seal it won’t alter the colour. I sealed mine with lithofin stain stop.

Oh , I actually have some of that , but it’s been in the cupboard for years …I wonder if it’s ok to use ?