Winckelmans 20mm and 50mm in the bathroom and shower? Here is what you need to know

Two sizes, one philosophy

Winckelmans creates mosaic tiles in various sizes — and two stand out as the most requested for bathrooms and showers: the 20×20mm and the 50×50mm. Small in size, big in character. Both are made of unglazed porcelain stoneware — grès cérame pleine masse — double-fired at approximately 1,200°C. The color pigment is integrated through the full thickness, not just in a thin top layer that wears away after a few years. These are tiles built to last longer than most marriages.

Why small tiles work so well on shower floors

A shower floor needs a slope — 1.5 to 2% inclination towards the drain so water doesn't pool at your feet. Large tiles struggle to follow that slope and require complex cutting patterns. Winckelmans' flexible mesh sheets bend effortlessly with the slope. No fuss, no compromises.

And then there’s the slip resistance. Individually, both the 20×20 and the 50×50 already achieve R10 on the official wear test. But once installed — with all those grout lines acting as micro-ridges — the classification climbs to R11. For barefoot wet zones, the natural finish scores class B (DIN 51097) — exactly the required classification for shower floors. The wet friction coefficient is 0.62 (required threshold: ≥0.40). More than enough.

20×20 vs. 50×50: which size fits where?

Technically, both sizes perform excellently in wet zones. The difference lies in the visual effect and the grout ratio.

The 20×20mm provides a fine-meshed, almost texture-like appearance — warm, artisanal, full of character. Per square meter, you'll have about 2,038 tiles with nearly 91 linear meters of grout lines. That’s approximately 18% grout surface. Those joints are functional: they guide water toward the drain and increase grip. But they also require more maintenance.

The 50×50mm looks a bit calmer and more modern, with fewer joints per square meter. It is still recognizably mosaic, but with a slightly sleeker look. The thicker versions (5 or 9mm) also make this format more suitable for floors with higher traffic.

130 years of craftsmanship from Northern France

A bit of backstory, because it’s worth it. Winckelmans is not a Dutch company, even if the name sounds like it. Founder Théophile Winckelmans — of Dutch descent — opened his factory in 1894 in Lomme, near Lille. Today, the fifth generation leads the company: Barbara Winckelmans. Same location, same craft.

The company carries the label Entreprise du Patrimoine Vivant — a French government award for companies that preserve living craftsmanship. They are described as the last European manufacturer of unglazed fully vitrified ceramic mosaic. With about 120 employees, they produce 700,000 m² annually in more than 50 shapes and dozens of colors. Their references? The Paris metro, Hermès stores, Disneyland Paris. And now, perhaps, your bathroom.

The downside: joints require attention

Let's be honest. Those many joints — the functional heart of the mosaic — are also the places where soap, limescale, and mold love to settle. This isn't a dealbreaker, but it requires conscious choices during installation and maintenance.

Maintenance and treatment: Fila MP90

Although the tile itself absorbs almost no water, the micro-structured unglazed surface can hold soap and limescale residue. Impregnation is therefore essential for shower applications — even if some sources claim otherwise. Winckelmans' own technical documentation is unambiguous: for heavily used wet surfaces, impregnation is required.

For the treatment of Winckelmans mosaic tiles in bathrooms and showers, we recommend Fila MP90. This is a professional, penetrating solvent-based sealer, specifically developed for unglazed ceramics and porcelain. It penetrates deep into the material, forming an invisible barrier against water, soap, shampoo, and limescale — and leaves the original matte appearance completely intact. No shine, no film, just protection you can't see but can feel.

How to apply Fila MP90

1. Wait 1 to 2 weeks after installation — adhesive and grout must be fully cured.
2. Clean the surface thoroughly and let it dry completely.
3. Apply Fila MP90 with a brush, roller, or sponge — work in small sections.
4. Let it soak for 10 to 15 minutes.
5. Remove any excess product with a dry cloth before it dries.
6. Let it rest for 24 hours before first use.

How often to repeat?

Daily maintenance? Simple: a pH-neutral cleaner and a squeegee after every shower. This prevents soap and limescale buildup in the joints — making your annual cleaning much easier.

Is Winckelmans mosaic for you?

Yes, if you...

• are building or renovating a walk-in shower and slip resistance is a priority
• choose long-term quality and are willing to invest in the correct finish
• want to combine a warm, authentic look with technical prowess
• are looking for a tile whose color and structure will remain the same after twenty years

Maybe not, if you...

• want absolute minimal maintenance and never want to scrub grout
• strive for a sleek, modern, and almost grout-free design
• have a tight budget — both material and labor fall into the premium segment
• insist on colored grout — technically, it just doesn't work here

The conclusion: small tile, big result

Winckelmans mosaic — in the small 20×20 or the slightly larger 50×50 — is not a tile for those who want the easiest path. It is a tile for those who want the best.

The combination of R11 slip resistance, near-zero absorption, exceptional hardness, and 130 years of craftsmanship makes it one of the strongest choices for shower floors and bathrooms in existence. The joints require attention, the installation requires skill, and Fila MP90 belongs as a fixed annual appointment for the shower.

But those who make that investment have a bathroom that will still be beautiful in twenty years. And that is more than you can say for most choices in life.