Different Types of Concrete Toppings

Often, these thin concrete toppings are used to spruce up worn and weathered concrete. However, they also provide a concrete-like finish over other floor materials like ceramic tile, slate, VCT or gypsum.

Unlike concrete, these thin overlays do not need to be bonded to the slab. They are commonly used when concrete surface preparation is impractical.

Polymer Modified

Polymers aren’t as colorful or visible as the pigments, acids and other raw materials considered in this website but they help thin concrete toppings hold together. They’re important, especially when they’re being used to resurface old, worn concrete floors or exterior hardscapes.

Polymer modified concrete (PMC) is a type of admixture that incorporates water-soluble or emulsified polymers into concrete mixtures to modify its properties. Unlike ordinary concrete, PCM requires less water, has higher abrasion and freeze-thaw resistance, and gains superior shear bond strength.

The polymers used to make PMC are typically styrene butadiene rubber, polyvinyl acetate or acrylic. These latex emulsions add workability, lower the water-to-cement ratio and increase flexural and tensile strengths. They also improve the resistance of concrete to chloride attack. PMC is often used for repair of existing concrete and to build new structures in cold climates where the structure will be exposed to freezing temperatures. It is also a popular choice for decorative applications.

Vinyl Acetate

Vinyl acetate is among the most flexible of the polymers used to modify concrete. Its inherent water resistance makes it a good choice for exterior applications in climates that experience extreme freeze-thaw cycles.

Its low hardness also means that it can be applied in thin layers, making it a practical option for renovation projects that require a topping that doesn’t interfere with doorjambs or other existing features of the structure. Unlike epoxy and urethane, vinyl acetate can be stained to achieve a specific aesthetic.

In its pure form, vinyl acetate is a clear liquid that has a sweet fruity smell. It is soluble in water and evaporates in air, though its vapors are heavier than air. It is highly flammable and can ignite in the presence of heat, sparks or flames. Its vapors can irritate the eyes and respiratory tract. Chronic exposure to this chemical may cause suffocation. Emergency decontamination and life-support procedures are necessary if exposure occurs.

Epoxy

Epoxy coatings are very popular with homeowners looking to upgrade their garage floors, as well as industrial and commercial facilities. They are highly resistant to chemicals and have excellent abrasion, impact, and scuff resistance.

Unlike paint, which is solid in color, epoxy resins are comprised of two components that must be mixed together to create a chemical reaction. If the epoxy is not mixed properly or the ambient temperature is too high, it can cause a condition known as blisters in the concrete floor coating.

Before applying any concrete coating, it is important to thoroughly clean and pressure wash the existing surface. If the concrete is not etched and free of contaminates such as mildew, grease, waxes, oils and other contaminants, it will inhibit the bond between the concrete and the new coating. An acid wash using muriatic acid or a safer alternative like DRYLOK is used to roughen the concrete and open pores so that an epoxy coat can adhere. Moisture testing is also critical, as it will affect how well the concrete coating can cure.

Urethane

Urethane, also known as cementitious urethane or polymer concrete, is a high-build coating that can be trowel-applied, roller-applied or self-leveled. It’s made from a combination of urethane, common Portland cement, aggregate powders and water. It requires no priming and can be applied directly over damp concrete. It’s available in fast turnaround versions for reduced operational downtime.

Urethane cement is a good choice for food and beverage facilities since it’s designed to handle the heavy traffic and chemical abuse of these environments. It’s highly hygienic, resistant to fungi and mold growth and provides a slip-resistant surface.

Like epoxy, urethane is hard and durable, but it’s typically not as tough as a resinous blend. While it does a great job withstanding impact and abrasion, it can be beaten up by heavy machinery or other heavy objects. It does better at resisting abrasion and harsh chemicals than epoxy but does less well with thermal shock or humidity. This makes it a good option for facilities that must meet strict sanitation standards, such as breweries or pharmaceutical manufacturing.

from Polished Concrete Newcastle Specialist https://ift.tt/gwPzfpR
via IFTTT