The easiest way to do this is to put some mixed grout on the tile and drag it across the joints at a shallow angle while pressing down. When all the joints are full drag the float at a steep angle across the tiles to remove the excess. Drag the trowel at an angle to the joints so that you don’t pull the grout.
After you remove the sufficient amount of the old grout just mix some new grout and fill the lines. You must make sure you force the new grout into the grout lines very well. You want to make certain there are no voids and the lines are full.
This of course begs the query “Can You regrout over existing Grout?”
When it comes to regrouting, the first thing to come to your mind may be to apply a new layer of grout over the old layer. Below are a couple of reasons you shouldn’t do this. Regrouting over existing grout means the new mixture may not properly adhere to the tile edges, exposing the material to water and potentially harmful substances.
The Grout Medic notes that new grout won’t adhere very well to old, dirty grout. Make sure you look for any problems that may have caused the grout to crumble or look particularly dirty or moldy. Solve issues that created problems for the old grout before you begin to do the work of laying down the fresh layer of grout.
Can You Make your own epoxy Grout?
This is what makes the grout more flexible. Many companies that sell their own acrylic-hybrid grouts will do this on their own, and also add a couple of other additives. If you want to make your own, you can. Several companies sell acrylic additives on their own.
Do you have to finish grout joints evenly?
Generally, a flush joint is desired on any square edged tile (including rectified tile), but the ANSI standard found in A108.10 section 5.3.4 states, “ All grout joints shall be uniformly finished. Cushion edge tile shall be finished evenly to the depth of the cushion.” Can you regrout floor tile 3 times?
How do you patch grout between tile and grout?
Grout bonds mostly to the tiles, less so to itself. If you dig the grout out, try to do it at a 90 degree angle to the “proper height” grout, this will give you the best adhesion for your patch. If possible try to make those 90 degree joins where there’s more tile to adhere to (avoid starting a new grout line at the corners).
Mix grout according to package directions. Spread the grout using the grout float, forcing grout into all joints and pulling the excess off with the edge of the float like a squeegee. Wash grout off the surface of the tile with a damp sponge while smoothing the joints at the same time.