Black Grout is a dark black color, but be aware that grout color is not as intense when cured as it is wet. Black makes colors stand out or "pop"
as they say. Use Black Grout for striking contrast in your mosaic, although a nice medium gray is probably a better choice if you're not sure. Unless
your tile is gray or a dull light blue, gray grout is almost always the safest choice of grout color.
Sanded? Unsanded? Epoxy?
Our grout is a conventional grout, which means that it is portland cement (anhydrous lime), sand and mineral pigments. It is not one of the new
epoxy-based grouts. Our grout is a dry powder pre-blended with sand. Just add water. Note that unsanded grout is only used for sealing hairline cracks.
Grout is almost never used without sand because you need sand. Sand gives grout tensile strength the same way gravel gives concrete tensile strength.
Should You Buy Grout Locally?
Our grout is small convenience packs for individual projects. Grout can be purchased locally in very large bags cheaply at building material stores, and
your don't have to pay shipping. If you are trying to grout a large mural or a whole class's mosaics, you should probably buy grout locally in
a large bag like building contractors use. However, the large bags are more difficult to pour without creating a lot of dust, which is a real safety issue,
and they are difficult to pick up, handle and store. There are reasons to buy our grout in the convenient tubs for small projects, but you should never buy
more than 3 or 4 containers. Instead, go to your local building material store and save money.
Choosing A Grout Color
Contrast. Don't Match
Grout can totally change the look of a mosaic, and it is possible to ruin (at least temporarily) a mosaic you have worked on for weeks merely by applying
a wrong color grout. Grout is supposed to CONTRAST tile color not match it. Visually, the purpose of the grout line is to separate the tiles. If your grout
color is too close to your grout color, then it all runs together visually and individual tiles do not stand out. (That is something that you won't like
once you see it.)
Grout As a Source of Color
While it is possible to color grout by blending artist acrylic paint with white grout, and it actually improves the strength of the grout, it is not
recommended. Why? In most mosaic, the groutline functions visually the same way as a pencil line functions in a watercolor painting: it is a linear element
that acts as a border and defines shapes but not as a source of color. Mosaics that rely on grout as a source of color almost always look more like
ill-conceived experiments than mosaics. Sure they are art, in the same way that a shopping cart full of mannequin heads is art, but do you really want
that in your living room?
There are mosaics where white grout is the best choice, but they are few and far between. White grout makes most mosaics look like a summer camp project,
and that probably isn't the look you are going for in your project. If you want a light grout, choose and antique white or eggshell white. It's great
that we have the technology to manufacture blinding white grout, it just doesn't look natural or flatter most tile colors. In general, darker grouts
usually make the tile colors look deeper and richer while white grout tends to make the mosaic look bleached out. When in doubt, avoid plain white grout.
How Much Grout Do You Need?
How Much Grout Do You Need? It depends as much on the gaps between the tiles as it does the total area. If your gaps are the standard 1/16 inch, and you are using
thin glass mosaic tile, then you will probably use less than 1 lb of grout per square foot. If you have thick tile with large gaps, you could use over 1.5 lb.
However, waste is a significant factor, and you have to budget extra for all the grout you will have falling off the sides of the mosaic when you smear it on.
We recommend grouting over a plastic dishpan so you can catch the droppings and pick them back up. For first attempts at grouting, you should be conservative
budget some extra for waste. Remember, a little wasted grout is better than a wasted mosaic!
Grouting outdoors is best, especially some place you can run a water hose and don't mind a little sand and residue being rinsed. Excess grout
could kill grass or plants, so scoop up what you can and wash away what is left.
Grout and concrete harden by BINDING water not by drying out. If you let grout or concrete dry out while it is curing, then it will be
soft and crumbly. This also happens if you did not add enough water to the grout when you mixed it up. Cover your mosaic with plastic if
you are grouting in strong heat, sunlight, air conditioning, wind or any other condition that accelerates drying.
Make sure you rinse all the water out of your sponge so that it is moist but not leaving drips of water when you rub it on the mosaic. You do not
want to get drips of water in the grout in the gaps when you are rubbing the residue off the faces of the tile.
Do not pour left over grout or grout sludge down plumbing or drains. Grout is concrete and can harden under water. Even sand can clog drains.
Instead, pour your grout and grout water into an old plastic container. After it hardens, you can pour off the water and dispose what is left
as solid waste.
We use traditional grouts and NOT the new epoxy-grouts, and all our advice is written for traditional grout. If you use the new epoxy-base
products, then make sure you read manufacturer recommendations for safety and disposal.
Always wear safety glasses with side shields when mixing and
applying grout. Grouting is a physical process with lots of mixing and rubbing and wiping, and these motions cause pieces of sand and grit to
Grout contains powdered silica (sand) and is slightly caustic due to the lime it contains. Avoid breathing the dust. Use a dust mask when mixing
or use a misting water bottle to avoid creating dust.
Grout can also irritate the skin, sometimes severely if you have sensitive skin. The sand and rubbing required in grouting further
aggravate this problem. Wear rubber gloves while grouting to protect your skin.
More How-To-Mosaic Information
For more advice on designing your mosaic project or cutting and grouting tile, please see our
Mosaic Frequently Asked Questions
or our List of How-to-Mosaic Pages, which are described by topic.