Microcement in bathrooms: a practical guide (waterproofing and application)

You can, and it is one of the uses where it shines most. In a bathroom, microcement delivers a continuous, seamless surface across walls, floor and shower, removing the main place where mould and dirt build up in a tiled bathroom: the grout lines. The result is a more hygienic bathroom that is easier to clean and looks more spacious. It is ideal for walk-in showers level with the floor, where the absence of a tray and joints creates a clean, modern space.

Microcement on its own is a porous coating; what makes it waterproof is the complete system and, specifically, the final sealer. That is why in areas of direct water, such as the shower floor, the prior waterproofing of the substrate and the choice of a high-performance polyurethane sealer are non-negotiable. When that system is executed properly, water runs off without penetrating and the bathroom behaves like a watertight, durable surface.

Yes. As long as the tiles are well bonded and sound, microcement is applied over them without removing them. The surface is cleaned and degreased, a specific bonding primer is applied and the tile grout lines are filled so they do not show through. From there, the microcement layers create a completely new, continuous surface. This is what makes it possible to renovate a bathroom in a few days, with no rubble and without turning the home into a building site.

1. Substrate preparation: cleaning, degreasing and repair of loose tiles or defects.
2. Waterproofing of the wet zones (especially the shower floor) with a membrane or waterproofing product.
3. Bonding primer over the existing tile or substrate.
4. Application of the base layers with reinforcing mesh at critical points.
5. Finishing layers, fine sanding and achieving the chosen colour and texture.
6. Final sealing with a high water-resistance polyurethane (one or several coats).

• Daily cleaning with neutral soap and water; avoid acids, concentrated bleach and metal scourers.
• Dry the shower surface after use to extend the life of the sealer.
• Renew the protective sealer from time to time depending on use, as preventive maintenance.
• Do not leave cosmetic products spilled on the surface for long periods.

• Skipping the prior waterproofing of the shower and relying on the microcement alone.
• Using a generic sealer instead of a polyurethane suitable for wet areas.
• Applying over loose tiles or unrepaired damp.
• Treating it as a DIY job: in a bathroom, the applicator's skill makes the difference.

If you are weighing up a microcement bathroom in Málaga or on the Costa del Sol, at GM Microcemento we deliver the complete system —waterproofing and sealing included— so your shower stays watertight and looks beautiful for years.