House builders are not just placing tiles on a naked base when they install tile flooring. They put a layer called tile underlayment, before finally placing the tiles on its flat surface.
While you may spend days thinking about the best tiles for a new floor, you also need to think about the underlayment. Not only it supports the tiles, but it also offers several benefits.
Here is a basic guide about tile floor underlayment you need to read before making flooring options.
1. What is Tile Underlayment?

An underlayment is an additional layer (or layers) that are added on the floor base to place tiles. The main function is to provide a flat surface for tile installation.
Almost all countries have regulations about building details, including the irregularities of a floor. If your floor base has an irregular surface, you must cover it with underlayment layer before installing the actual floor.
You can install underlayment yourself with a DIY project, especially if your floor base is already flat enough. However, if your lot has a really uneven surface, hiring professional service is a good idea.
This is to ensure that the underlayment for tile can support the floor burden, while still following regulations.
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2. Reasons to Install Underlayment Layer

Creating even surface is not the only reason to install an underlayment layer. Here is why you need to install tile underlayment:
Leveling the floor
When you construct a floor on a certain height, you need to level the surface before installing the tiles. Adding underlayment layers will help you reach the desired floor height.
Preventing moisture penetration
Moisture can rise from inside the floor to the surface, creating stains and other unsightly views on your tiles. If you have “soft” tiles such as vinyl sheets or travertine, moisture can damage them after several years.
Underlayment stops the moisture to seep upward.
Supporting the load
Installing tiles when adding extra load on your floor base. The load becomes bigger if you install heavy tiles such as granite or marble.
The best underlayment for tile not only supports the tiles, but also keeps the integrity of your base. Durable underlayment layer can also prevent tile or base cracks.
Reducing the risk of tile lippage
Uneven tile ridges (lippage) can happen because of several causes, one of them is uneven floor base. Tile underlayment helps reducing lippage risks, helping you to get smoother floor surface.
Reducing noises and adding comfort
A good underlayment layer can help reducing noises, especially if you live in an urban area. It also provides “cushion” for your tiles, so walking can feel more comfortable in the house.
Products such as DITRA Tile Underlayment not only provides support for the tiles, but also adds functional benefits to your house.
3. Types of Tile Underlayment Layer

Underlayment layer has become popular since the olden days of architecture. In the early modern North America, mortar bed was the most popular underlayment for a tiling floor.
However, this material is now ditched because of its weight and long installation process.
There are many good alternatives to tile underlayment products. Here are some of them:
Cement or cement board
Cement is one of the most popular tile underlayment options around the world. It is cheap, easy to get or mix, and can provide strong base support.
You can pour it directly to the base or use cement blocks for quicker installation.
Liquid underlayment membrane
Liquid underlayment membrane is a modern invention with easy application. It is lighter than poured cement but providing perfect sealant and supporting layer for the tiles.
This product usually dries in 12 years.
Plastic uncoupling membrane
Plastic uncoupling membrane looks like layers that have mesh patterns on top of them, which secure the back of the tiles. This membrane separates the top tile layer from the base.
It also reduces moisture risk and vapor pressure.
Concrete
Underlayment for tile on concrete is basically similar with the cement one. You get a durable layer with a flat surface, perfect for installing large and small tiles.
Exterior-grade plywood
Exterior-grade plywood was created to handle extreme weather and temperature. Therefore, it is a good option to handle a problem such as moisture.
4. Don’t Install Tiles on These Underlayment Types!

There are many types of underlayment lawyers sold in the global market. However, some of them are unsuitable for a tile floor. Examples are:
Drywall
Drywall is one of the most uncommon underlayment materials, but it is unsuitable for tiles. The pain may peel off and reduce the look.
Vinyl tiles
Underlayment for vinyl tile can be made of the same material. However, the ideal vinyl for underlayment is the sheet one. Vinyl tile underlayment can cause moisture problem (seeping between the grout lines).
The vinyl tiles can also shift, creating unsightly.
Particle board
Particle board is easy to install and providing even, durable surface. However, particle board can be very happy, especially when combined with other materials and the actual tiles.
Interior-grade plywood
Unlike exterior-grade plywood, the interior grade one has a tendency to swell after years. This is due to factors such as fluctuating temperature, continuous heat exposure (such as from the sun), and moisture.
This plywood is unsuitable for all floor materials, because it is fragile.
When choosing porcelain or ceramic tile underlayment, make sure you determine the actual needs for the underlayment, and how you will apply it (if you do everything alone).
There are several reasons why we need to install tile underlayment layers. They range from reducing vapor pressure and moisture to preventing noises from permeating.
Popular underlayment materials include exterior-grade plywood, uncoupling membrane, cement, and concrete (the latter is perfect for porcelain tile underlayment due to a flat surface).
Some materials may be unsuitable to be turned into the underlayment layer, such as vinyl tiles, interior-grade plywood, and drywall.
Aside from choosing the right materials, the best option is to hire a professional service to install the underlayment.
Make sure you determine the best tile underlayment materials based on your personal characteristic.