Replies

1. 
   DanH | Mar 28, 2010 07:31pm | #1

   Darn, you had to add that last qualification, didn't you??

   The standard approach is a "grout saw" -- a sort of oversized toothbrush handle with a bit of saw blade attached instead of the bristles.  Readily available at a Big Box or tile store.

   Quicker is either a Dremel with a large abrasive wheel or (better) a Multimaster (or clone) with an abrasive blade (though these options don't work well on narrow grout lines).  For really wide grout lines you can even get away with a regular circular saw with an abrasive blade.

   Of these options, only the manual grout saw works very well on caulk, if you have some of that to remove.

   If you're only replacing the grout due to staining, note that you only have to remove maybe 1/16" of grout (maybe 3/32" for sanded grout) in order to make enough of a depression to regrout.  (For this duty sometimes the Dremel with something resembling dental drill will work.) 

   But note that if you're removing the grout because it's cracked there's a good chance that the reason for that is that the tile backer has gone punk and to the whole thing needs to be torn out and redone anyway.

2. 
   Clewless1 | Mar 29, 2010 08:04am | #2

   What Dan said ... yeah it's a lot of work sometimes, but may be the only practical option. As with many things you try the various available known techniques and then begin to discover what works best for you ... and then add some of your own variations.

   Are you doing a large area or just a few grout lines?