What Type of Grout Is Used on Tile Joints in a Shower?

If you are putting in a new shower, you probably long for easy answers about what products to use and what to avoid. For example, tiled showers are very popular. You may have picked out some beautiful tile and wonder what type of grout to squeeze into the joints between the tile squares. Unfortunately, there is no one type of grout that works best for all shower-tile situations. So when you ask for the best type of grout for shower joints, the most accurate answer you can get is: It all depends.

Woman standing in shower, low section
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What Type of Grout Is Used on Tile Joints in a Shower?

Shower Grout Basics

Although there may be a few eccentrics out there who install showers purely for ornamental purposes, most people use showers to get their bodies clean. That means that the material on the shower walls must be waterproof. Tiles are a very popular choice for shower walls and bathroom walls in general. They come in a range of options, from standard, economy ceramic squares to exquisite Italian-made tiles. But since multiple tiles are required to fill a wall, the spaces between the tiles must be sealed to make the wall covering waterproof. This is where waterproof grout comes in.

Grout is the product you use to fill the cracks between tiles, called joints. Sometimes you can squeeze it in like toothpaste, but in other cases, you might use special tools to get it into the right spots. The material you use to fill the area between tiles and tub or tiles and shower drain is not grout but caulk. It too must be waterproof to prevent potential rot issues.

Sanded vs. Unsanded Grout

When it comes to shower grout, the first choice is between sanded and unsanded grout. Note at the outset that this doesn't refer to whether you have to pass afterward with sandpaper. Rather, sand is a component of sanded grout, while unsanded grout – also called non-sanded grout – has no sand in it.

Basically, the choice will be made for you by the width of the grout lines between tiles. If those joints are bigger than 1/8-inch wide, you'll have to use sanded grout. Grout without sand in it shrinks as it dries. In larger joints, non-sanded grout shrinks enough to pull back from the tiles. It should only be used in small joints, those 1/8-inch wide or smaller.

Epoxy Grout or Cement Grout

But sanded vs unsanded grout is just one of your choices. You'll also have to decide between epoxy grout or cement grout. The traditional grout is cement-based, and it has been the default grout for years. It comes in both sanded and unsanded versions and is very affordable and easy to use. However, its surface chips, stains and molds easily, so you'll have to seal it after it has cured and dried completely.

Epoxy grout is the new kid on the block, made of epoxy resins and a filler powder. Very tough and durable, it doesn't stain or require sealing. It also dries much quicker than cement-based grout. The downside? It is quite pricey.