What Type of Grout is Best for Tiles Under Resin?

Why Epoxy Grout Stands Out

Epoxy-based grout, or specialist mastic, is highly recommended when grouting tiles that will be coated with resin. Unlike traditional cement-based grout, epoxy grout offers superior bond strength and is resistant to moisture, stains, and chemicals. This makes it particularly suitable for use in bathrooms, kitchens, outdoor spaces, or high-traffic floors where long-term durability is key.

If you are looking for a practical solution, Magelstick Epoxy Mastic is a reliable choice, designed for excellent mechanical strength and stability even on vertical surfaces.

Application Tips for Lasting Results

Before applying resin over tiles, ensure that your grout lines are clean, fully cured, and free of dust or loose particles. Use a bi-component epoxy mastic, following the manufacturer’s mixing ratio and recommended application temperature (generally above 10°C for best results). For a stable substrate, pair your grout with a suitable primer such as Epoxyprimer before pouring the resin layer. This boosts adhesion and helps avoid future delamination or surface issues.

When Does Grout Choice Matter Most?

Choosing the right grout is especially important for surfaces exposed to water, temperature fluctuations, or regular wear—think showers, patios, or kitchen floors. Epoxy-based options are less likely to crack or absorb moisture, ensuring that your resin finish remains intact and attractive over time.