4 Most Common Mistakes When Choosing and Applying Concrete Polished Plasters

1) Choosing the Wrong Type of Polished Plaster for the Space

Not all concrete polished plasters are the same. We distinguish two main types – cement-based polished plasters and epoxy polished plasters with a concrete look.

• Cement-based polished plasters (e.g. Imitace betonu®) are best suited for walls. Their water resistance depends entirely on the protective lacquer, which means they are not suitable for shower enclosures or floors. If the lacquer becomes damaged over time, the plaster starts absorbing moisture, stains will appear, and the surface may begin to peel.
• Epoxy polished plasters (e.g. Betonepox®) are waterproof and resistant to chemicals. They are ideal for floors, bathrooms, and even directly inside shower enclosures, where ordinary cement-based plasters fail.

Tip: Always seek professional advice when choosing a finish. Selecting the right polished plaster for the specific area is the foundation of a long-lasting result. In permanently wet areas, always choose an epoxy polished plaster, not a cement-based one.

2) Poor Surface Preparation

If the substrate is not properly prepared, you can’t expect a good result. Dust, grease, unevenness, or remnants of old coatings reduce adhesion. Even more critical is the use of a strong, high-quality adhesive, which ensures proper bonding between layers and the long-term durability of the plaster.

Tip: The substrate must be solid, clean, and dry. Proper preparation – grinding and mesh reinforcement – is essential. An experienced applicator will never skip these steps.

3) Prioritising Price Over Quality

Polished plaster is not only about appearance – differences in quality often become apparent only over time. Cheaper solutions usually mean cheaper materials, which are less durable and have a shorter lifespan. Such plasters can gradually lose their look, change colour, or stop providing proper protection – especially on floors and in bathrooms, where surfaces are under the greatest strain.

Tip: Don’t focus on price alone. High-quality materials are an investment that pays off in long-term durability and easy maintenance.

4) Working with an Unverified Company

Polished plasters require skilled hands and a sense of detail – every movement of the trowel affects the final look. Knowledge of correct application techniques and attention to key details, such as expansion joints between walls and floors, are absolutely essential. If these steps are neglected, the surface may eventually crack or start to peel. A small initial saving can later lead to damage costing tens or even hundreds of thousands.

Tip: Choose a company with many years of experience, one that understands the technology, uses high-quality materials, and has a proven record of successful projects.

A concrete polished plaster can be a beautiful and durable solution – provided the right type of material is chosen, the substrate is properly prepared, and the work is carried out with attention to detail. The difference between a surface that lasts for years and one that starts to peel lies in the quality of materials, expertise, and experience of the applicator.

Němec s.r.o. has been applying polished plasters for nearly 30 years, completing thousands of projects, and thanks to its own time-tested technologies, guarantees quality, design, and a professional approach. We provide a 5-year warranty on all applications, and thanks to our post-warranty service, we can easily repair even older projects.

Visit our showrooms in Prague or Brno. We’ll be happy to show you the different finishes and help you choose the most suitable solution for your interior.