Introduction
When it comes to tiling, the old adage “a house is only as strong as its foundation” couldn’t be more apt. While the choice of tiles and their arrangement are crucial for aesthetics, it’s the surface beneath that often determines the longevity and quality of the installation. This is where underlayments and levelling compounds come into play, serving as the unsung heroes of successful tiling projects.
A smooth, level surface is essential for several reasons:
- It ensures proper adhesion of tiles, preventing loose or hollow-sounding tiles.
- It helps distribute weight evenly, reducing the risk of cracks or breakage.
- It contributes to the overall aesthetic appeal by preventing lippage (unevenness between adjacent tiles).
- It can improve the water-resistance of the tiled surface, especially in wet areas.
Underlayments and levelling compounds are the tools that allow us to achieve this ideal surface, even when working with less-than-perfect substrates. In this article, we’ll explore what these materials are, when to use them, and how they contribute to creating the perfect base for your tiling project.
Understanding Underlayments
What are Underlayments?
Underlayments are materials installed over an existing subfloor to create a smooth, flat surface for tile installation. They serve multiple purposes:
- Leveling out minor imperfections in the subfloor
- Providing additional height to match adjacent flooring
- Improving the bond between the subfloor and the tile
- Adding strength and stability to the overall flooring system
Types of Underlayments
There are several types of underlayments commonly used in tiling projects:
- Cement-based Underlayments
- Composed of Portland cement, sand, and polymer additives
- Pros: Durable, moisture-resistant, suitable for most tile types
- Cons: Require mixing, longer curing time
- Gypsum-based Underlayments
- Made from gypsum and other additives
- Pros: Self-leveling, quick-drying, lightweight
- Cons: Not suitable for wet areas, may require special primers
- Foam Tile Underlayments
- Typically made of extruded polystyrene
- Pros: Lightweight, insulating, crack isolation properties
- Cons: Not suitable for all tile types, can be more expensive
When to Use Underlayments
Underlayments are particularly useful in the following situations:
- When the existing subfloor is not smooth or level enough for direct tile installation
- To raise the height of the floor to match adjacent surfaces
- When additional sound or thermal insulation is desired
- To provide a moisture barrier in areas prone to dampness
- When installing tiles over existing vinyl or other non-ideal surfaces
It’s important to note that the choice of underlayment should be based on the specific requirements of your project, including the type of substrate, the intended use of the space, and the type of tile being installed.
In the next section, we’ll explore levelling compounds, which are often used in conjunction with or as an alternative to underlayments for creating the ideal tiling surface.
