Grout Issues

Hi there. Just a quick question regarding grout. We just tiled our tub surround with 12X12 tiles w/ 1/4" grout lines. We tested a sample of the color grout we liked, but when it dried, it was really light(it was supposed to be a dark pewter) and had white spots all over it. So, I researched your site and found that too much water during cleanup and during mixing can cause this. So, in preparation for grouting our new surround, I made sure to wring every sponge completely dry and mixed the grout to a paste, but not runny or pourable. I followed every direction to the tee. Well, the grout has still dried significantly lighter(almost white or very lightish grey), but it doesn't have the white spots like our sample did. What did I do wrong? I love the color grout when it was wet, and this new color is I guess acceptable but I'm getting ready to do the floor with the same grout and want it to work right. Plus, I'm worried that our color matched caulk will now not match. Help!

 

What you described is very common, especially with those silvery grey grouts. Almost all of them dry lighter than the sample..in other words, you probably didn't do anything wrong. It may darken over time, or you could have some effloresence on the surface of the grout.(white minerals and latex and other stuff that rises to the top of the joints)
You might want to try washing the tile with a 50/50 solution of white vinegar and water. This will sometimes remove some of the effloresence.

 

Thanks for the reassurance! I'll try the vinegar!

 

Grout generally will dry lighter than when it is wet. The water you use can have a big effect on the grout too. I live in an area where there are a lot of minerals in the water and it really does crazy things with grout color. I also have found that grout sealer generally darkens the grout a little too. Of course with time, the grout gets dirty and looks darker too. Grout never looks like the samples do. You might want to try a shade darker grout too.
Good Luck
Bryan

 

Sulfamic acid crystals will take care of efflorescence, if you are not happy with the color and it's all iniform, you can try an enchancer to darken it some, but try this in a small area first to see the results, if not happy, a grout colorant will give you whatever color you want and seal it all in one step, but you can not aplly the colorant over sealed grout, this is why, if you try the enchancer, test it first.