Flooring and Carpeting/Adura luxury tile grout
Hi Mr Adams, In the end of 2010 I had a flooring outfit lay down 2000 sq feet (yes 2000) of grouted adura luxury tile from Mannington. Not sure what happened Mannington says one thing and the floor dealer says another but the grout has as of this past summer .... shrunk... bad... over approx. 75 % of the floor. Cracks everywhere.
My question is should I let the floorer grout overtop of the existing grout or have it all taken up and new grout laid. Some of the cracks around the edges are miniscule while some are a couple of mm wide.
Based upon photo 2 it appears that your grout is shrinking, as opposed to cracking. Cracking is from movement (tile, subfloor, etc. ) Shrinkage is a moisture related issue; a) too much liquid is used during mixing. This makes for easy grouting, but poor results. Grout has to have enough body so that it can be packed into joints. If it is too loose, it will simply squeeze out of the joint. When it dries, the receding moisture leaves voids in the grout which cause it to be weak. b)too much water during cleaning will also cause weak grout.
A little grout background: Unsanded grout is made specifically for grout lines smaller than 1/8 inch wide (which if I had to guess is what they used on your floor). This is a general rule. It's much safer to use unsanded grout only in tile with grout lines smaller than 1/16″. Unsanded grout (all grout to different degrees) will shrink as it cures. The reason for only using it in smaller grout lines is the wider the grout lines, the more grout must be used to fill them. The more grout you have, the more it will shrink. If you try to fill grout lines that are too large the grout will shrink enough to pull away from the sides of the tile. Unsanded grout is easier to work with, especially on vertical surfaces such as a shower wall, because it is “stickier” than the sanded variety. You can spread it onto the wall and it will stick there while you force it into the grout lines. It is also much easier on the hands than sanded. Although it is easier to work with, you need to make sure that the application for which you are using it is correct.
Bottom line here: If this was my floor, and assuming they used the correct grout, I would have them try to fill the spaces before replacing all the grout, because 1). it might work and 2) it will be difficult to remove the existing grout without damaging some of the tiles, not to mention the time and mess involved.