The Grouting Bag is made from latex-rubber-coated reinforced canvas and is puncture and tear resistant for durable use with concrete products such as grouts and mortars. The bag is large, about 22 inches long, so it can hold 5 to 8 pounds of grout easily, depending on your preference. (We prefer to use less and keep the top of the bag cleaner where you twist it closed.) The purpose of the bag is for applying grout in areas where you have to work a little neater or in places that are harder to reach, such as the tops of walls near the ceiling. Ask any installer, and they will tell you: squeezing a controlled amount from a bag is neater than lifting wet grout on a trowel, especially when working over head, unless you don’t mind clumps of concrete falling in your hair!
- material: reinforced canvas coated with latex rubber
- length: approximately 22 inches
- capacity: approximately 8 pounds
- closure: twisted by hand, using clips or clamps recommended
- nozzle: simple opening in the end of the bag
How to Use the Grouting Bag
A grouting bag works just like an icing bag that is used for icing cakes. The only difference is that it is larger and doesn’t come with different nipple attachments. The end of the bag is twisted to close it up and squeeze it, and we have found that a plastic carpenters clamp is useful for keeping the bag twisted closed when you sit it down. (If it twists open, it can get a little messy when you twist it closed again.)
Use for Detailed Mosaic Art
The normal use of the Grouting Bag is for getting grout neatly into architectural crevices and corners that are too confined for trowel work. We use the Grouting Bag for much more detailed work than that. Specifically, we use the bag for cementing irregularly-shaped artifacts in found-object mosaic using thinset mortar. To use the bag for this purpose, we attach a small diameter nozzle from a Wilton brand cake icing kit, which allows us to apply smaller amounts of mortar in a more controlled way.
To get the nozzle tip of a cake icing kit to stay on the grouting bag, we have to improvise a little bit: We trim some of the tip of the bag off so that the nozzle can fit through the opening. Then we put rubber bands around the plastic collar holding the nozzle to help it stay on. The finished assembly looks home made, but we have found it to be highly effective for dispensing controlled amounts of thinset mortar on tiny objects without contaminating them. Note that rags are still required for cleaning up occasional mistakes, and a set of palette knives is also useful for manipulating and spreading material.
Tip: the icing nozzle has a small diameter and tends to get clogged occasionally, so keep a nail or piece of wire to clean it out. We have also written some instructions for how to use thinset mortar for detailed mosaic artwork.
Loading Without Contaminating
The most important tip we can give in using the bag is to keep the top of the inside clean where you will need to twist it closed. How do you do that and still get the sticky grout or thinset inside? Pull the top of the bag down so that it is inside out, but don’t pull the bag all the way inside out. Then sit the bag tip down in something that can hold it upright as you scoop grout or thinset into it. We sit our bags in plastic quart-sized yogurt tubs and coffee cans and other recycled containers, and then we fill them and then fold up the top of the bag so that it is no longer inside out. Then we twist the top of the bag closed and clamp it and get to work.
Always wear safety glasses with side shields when mixing and applying grout. Grout is mildly caustic and contains little pieces of sand. Grouting is a physical process with lots of mixing and rubbing and wiping, and these motions cause pieces of sand and grit to fly unexpectedly.
How To Make Mosaics
For more advice on designing your mosaic project or mounting, cutting, and grouting tile, please see our page of Mosaic Frequently Asked Questions or our Mosaic Information Guide, which lists instructional pages described by topic. We also post new articles about making mosaics at our How to Mosaic Blog.