How to choose a microcement varnish to effectively protect the surface?

Microcement floors and walls are gaining popularity. This is due to the general trend toward minimalist and industrial designs, which microcement perfectly fits into. Additional advantages include the unique nature of floors made from this material and its wide color range.

At the same time, for a microcement floor to be pleasing to the eye for years to come and be easy to clean, it must be properly protected. A surface unprotected with polyurethane varnish will be highly absorbent of water and other contaminants and will be prone to dusting. The conclusion is clear – all microcement surfaces require additional protection. Which varnish should you choose?

Microcement varnishes vary depending on the place of application 

polyurethane varnishes available on the market makes choosing difficult. It's worth considering where the surface will be used first, and taking into account the intensity of use depending on the room type. The approach for walls and floors , and for wet areas or offices.

First of all, you need to answer the question: what kind of coating finish are you interested in? The surface can be:

• fully matte,
• semi-matte,
• in full shine.

Painting microcement on the wall

When painting microcement walls, it's important to pay close attention to the visual aspect. Matte varnishes are best suited for this purpose. They reflect less light, eliminate glare, and give the surface a more natural, concrete-like appearance. Neodur Varnish W Mat , with its deep matte finish,

Floor varnishing

When varnishing floors, additional attention should be paid to the chemical and mechanical resistance of the surface. This is particularly important for applications in offices (mechanical resistance) and, for example, kitchens (chemical resistance). For mechanical resistance, pay attention to the Taber test results. For chemical resistance, consider the substances the floor may be exposed to and check whether the varnish is resistant to the substances used.

Concrete varnish and abrasion resistance, or what does the Taber test mean?

Unfortunately, not every concrete varnish available on the market offers information on abrasion resistance. Abrasion resistance is tested using the Taber test. This test involves measuring the mass loss of a test sample during a test cycle. The lower the result (given in mg, or milligrams), the more abrasion-resistant the material .
Below, you can see a comparison of the abrasion resistance of Neodur Varnish, Neodur Varnish W Mat , and one of the varnishes available on the market.

How to properly apply polyurethane varnish to concrete?

When protecting microcement or concrete, the knowledge and skills of the painter are crucial. Proper conditions must be maintained during paint application. The temperature of the substrate, air, and paint itself should not exceed 12-35°C.

It's bad practice to apply varnish in too thick layers – this can result in visible roller marks. Apply varnish in thin layers using a suitable roller (short-napped and solvent-resistant). The roller itself should not leave bristles during application. To prevent this, you can wash the rollers with water the day before or remove loose bristles with masking tape. It's crucial to apply varnish in adequate lighting. Because varnishes are colorless, it's difficult to apply them correctly in poor lighting conditions.

Depending on the desired effect, it's also worth considering using a system primer. It evens out the absorbency of the substrate and preserves its natural appearance. Applying a solvent-based polyurethane varnish directly to the substrate, without primer, will create a wet concrete effect. 

Product preparation 

Polyurethane clearcoat for concrete and microcement is a two-component product, meaning it consists of a base coat and a hardener. Of course, it's important to mix the ingredients properly; it's important not to confuse the weight and volume ratios. A weight ratio means that the ingredients should be weighed on a scale before mixing. A volume ratio, on the other hand, means that the appropriate amount of ingredients should be measured in milliliters/liters beforehand, for example, using a mixing cup for paints and varnishes. 

If the mixing ratio is incorrect, the varnish may not cure completely or may have a shorter application time. Mixing ratios for Neodur Varnish are given by weight.

Choosing the right varnish to protect microcement surfaces is crucial to ensuring a pleasing finish. The quality of the finish is also crucial.