Notes about Grout

From Chapter 3:  Grouting Secrets and Tips (preview)

Grout and mortar appear to be similar, but they’re not. The chemical reaction for each is different, as well as the end result after these substances have dried. Generally, I don’t provide exact measurements for water/additive ratios for grout or mortar. This is disconcerting to my students; we all like to be able to follow a recipe. However, after 12 years of working with this craft, I have found that a number of factors affect how much water to use with grout, from the heat and humidity of your environment, to the type and brand of grout used, and even a difference in batches within the same brand of grout. 

Altitude and other factors, some apparently very mysterious, can cause fluctuations in liquid requirements. So if I did provide exact measurements for the amount of water or additive to mix with your grout, the recipe would be unreliable about 75 percent of the time. 

Certain types of grout call for mixing with either water or a grout additive. Recently I’ve noticed that many grouts only call for water, because the chemicals formerly contained in the additive are now mixed with the dry grout. The benefit of mixing an additive to grout that does not have these additives is that it makes the grout stronger and more pliable. Currently, I use Polyblend grout. Visit the Polyblend website for more detailed information about this product, and to view their color chart.  

NOTE: I do NOT recommend pre-mixed grout. 

The first rule of grout is this: Never wash grout, either wet or in dry powder form, down your drain, because it will ruin your pipes. I always use plastic containers to mix grout, and then discard the container after use. You can re-use plastic containers by popping out the dried grout after use. I use paper towels and old rags to wipe off grout during the grouting process, and then discard those materials after use. The color of grout used depends upon your personal taste, but my rule of thumb is this: Pastel shard colors stand out more with darker brown grout, bright colors really “pop” with white or off-white (sometimes labeled “antique white”), and black grout makes a stunning mosaic when really bright colors are used.