If you’re about to lay a new tile floor at home, selecting your preferred tiles is only one part of the process. Equally as important is your consideration of the subfloor upon which the tiles will be laid, as well as the level of underlayment that sits between.
But what different types of underlayment can you use? And how do you select the perfect type of tile underlayment for your subfloor?
We answer these questions and more in this article as we present an informative guide on how to pick the right tile underlayment for your home flooring project.
What is the Purpose of Tile Underlayment?
Tile underlayment is the middle layer of your tile floor and sits between the subfloor and the surface tiles that you walk upon when the floor has been laid. The primary role of tile underlayment is to smooth out any uneven points in your subfloor to enable you to lay your tile floor on a flat surface.
What’s more, underlayment acts as a waterproof barrier between your tile surface and the subfloor beneath, which is ideal if you’re planning to lay a tile floor in the bathroom or kitchen, where moisture levels are high. (Related: Do You Need An Underlayment For Tile On Concrete? (A Comprehensive Guide))
But as we explain below, there isn’t just one type of tile underlayment worthy of your consideration, and the various products can be separated into three broad categories.
The Three Primary Types of Underlayment for Tile Floors
It’s really important to understand the different types of tile underlayment, so you can pick the product that works best for your subfloor and chosen tiles. We introduce each type of tile underlayment below and help you decide which is the best option for your project.
1. Backer Boards
Backer boards have been around for decades and are among the most popular type of tile underlayment. They’re favored by professionals laying ceramic or porcelain tile floors and are typically comprised of cement, fiberglass, and crushed glass particles.
According to the Tile Council of North America, there are several different types of backer boards that you can use, including:
Each type of backer board introduced above can be used as tile underlayment, but an additional layer of thin-set mortar is required to affix the underlayment to the subfloor, which is a process in the industry known as bedding.
Backer boards have long been a popular choice when installing tiles, as they serve as an excellent bridge for your surface tiles and prevent them from cracking once laid.
2. Floor Underlayment Preparation Materials
If your subfloor is relatively flat and blemish-free, you don’t necessarily need to install backer boards before laying your tiles. There are several different preparation materials you can use for underlayment, as we introduce below.
3. Membranes
The third and final type of tile underlayment you can apply to the subfloor is a membrane. Membranes are made of polyethylene and typically come in rolls, which are designed to protect your floor from moisture and cracks.
There are several different types of membranes that can be added to your subfloor, and the product that you opt for depends on where you are laying your tile floor, as we explain below.
Choosing the Right Type of Tile Underlayment for Your Subfloor
As you can see from our extensive list of tile underlayment types, there are multiple options to choose from. And there isn’t universal agreement on which type of underlayment is the best, as every floor is slightly different from the next.
In order to choose the right type of tile underlayment, you first need to consider the condition of your subfloor, as this will often dictate what type of underlayment to proceed with. For instance, if you’re laying tiles on a perfectly flat concrete surface, a layer of thin-set mortar should do the trick.
But if the surface is damaged or cracked, you would be better served opting for a backer board or an uncoupling membrane as your underlayment.
You will find that the tiles that you choose come with a manufacturer’s recommendation, too, so you can use this to guide you as you look to lay your new tiles. But if you’re really struggling to come to a decision about which underlayment to opt for, it’s a good idea to consult a tiler or fitter to advise you and perhaps assist you with the project.
Final Thoughts
Unfortunately, it’s impossible to recommend one type of tile underlayment over another, as your choice will depend upon the condition of your floor and the specifics of your project. That being said, we hope this guide provides you with the information that you need to proceed with your DIY tile project or highlights the need for you to consult a professional!