Guide | Why Sealant Matters

Why You Should Seal Raw Clay Tiles

Raw clay tiles bring an earthy, rustic charm to any space, with their natural texture, tonal variation and organic appeal. Unlike glazed tiles, raw clay is naturally porous, meaning it can absorb water, oils, dirt and other liquids into its surface. This natural porosity is part of what gives clay tiles their beautiful, tactile character, but it also means they require a little more care and consideration than a glazed or non-porous tile.

Sealing your clay tiles is an important step in protecting their beauty, making them easier to maintain and helping them perform beautifully for years to come. While sealing won't change the fundamental nature of the clay, it can provide an important layer of protection against everyday spills, moisture and staining.

The Importance of a Sealant

Raw clay tiles are absorbent by nature. When left unsealed, liquids can penetrate directly into the pores of the tile, which can lead to staining, darkening and, over time, changes to the appearance of the surface. This is particularly important in areas such as kitchens, bathrooms, entryways and other high-traffic spaces where tiles are regularly exposed to water, food, oils, dirt and general household use.

A suitable penetrating sealer works by entering the pores of the clay and reducing its absorbency, rather than simply creating a thick coating over the surface. This makes it possible to protect the tile while maintaining much of the natural, raw appearance that makes handmade clay so beautiful.

There are different types of sealers available, and they do not all create the same result. Some are designed to penetrate into the tile while leaving the surface looking natural and matte, while others can create a more noticeable finish and may deepen or enhance the colour of the clay. Choosing the right sealer therefore depends on the tile, its intended application and the aesthetic you want to achieve.

For a raw, natural look, a high-quality penetrating sealer is generally the preferred approach. However, the sealer should always be tested on spare tiles before the entire installation is treated, as the final appearance can vary depending on the porosity, colour and composition of the clay.

A Simple Demonstration

One of the easiest ways to understand the importance of sealing is to see what happens when water comes into contact with raw clay. Imagine pouring a small amount of water onto an unsealed tile. The water will begin to absorb into the porous surface, often causing the clay to temporarily darken. If the tile is properly sealed, the water will generally sit on the surface for longer, giving you time to wipe it away before it can penetrate deeply into the clay.

This simple demonstration highlights one of the main benefits of sealing: it gives you greater protection against everyday spills and makes the surface considerably easier to care for. A water-drop test can also be used over time to assess whether an existing sealer is still providing adequate protection. If water continues to bead or sit on the surface, the sealer is likely still doing its job. If water begins to absorb quickly into the clay, it may be an indication that the tile requires another application of sealer.

Seal Before you Grout

One of the most important considerations when installing raw clay tiles is the timing of the seal. Because clay is porous, grout can be absorbed into the face of an unsealed tile. This can be particularly noticeable when using a contrasting grout colour, as the pigment can penetrate the surface and leave marks that are difficult, and sometimes impossible, to remove.

For this reason, raw clay tiles are generally best pre-sealed before grouting. Once the tiles have been installed and the adhesive has properly cured, a penetrating sealer can be applied to the tile surface before the grout is introduced. The sealer should be allowed to cure according to the manufacturer's instructions before grouting begins. Pre-sealing acts as an important grout release, helping to prevent the grout from becoming embedded in the natural pores and texture of the clay. This is especially important with handmade tiles because their natural variation means that different pieces can have slightly different levels of absorbency. The aim is not to completely seal the tile beneath the grout, but to provide enough protection to prevent the grout from unnecessarily staining the face of the tile. Care should also be taken to remove excess sealer from the surface during application so that it does not leave a visible film or residue.

Does Sealing Change the Look of Raw Clay?

One of the most common concerns when sealing raw clay is whether the process will take away its natural, earthy appearance. The answer depends entirely on the type of sealer used. A penetrating sealer designed to maintain a natural finish can provide protection without creating a glossy or heavy coating over the surface. Other products can deepen the colour of the clay or introduce a subtle satin appearance. Neither is necessarily right or wrong; it simply depends on the look you are trying to achieve and the fiunction you want the sealant to have

The most important rule is to always test first. Apply the proposed sealer to a spare tile and allow it to fully cure before making a decision. What appears subtle when first applied can become more noticeable once the sealer has dried.