Proper preparation is the first requirement for a polymer flooring installation. If preparation of the substrate is not done adequately, there is a significant chance of issues occurring, such as bonding to the substrate and other problems.
Concrete must be mechanically prepped utilizing diamond grinders, media blasting or scarifying. This is critical in order to remove the laitance and any potential contamination from the surface of the concrete. Laitance is the thin weak layer on the surface of poured concrete created from the drying process. Bond strength to the concrete without removal is typically less than 50 pounds per square inch (psi) bond strength. With removal, it is typically greater than 250 psi depending on the strength of the concrete.
Mixing of all materials is critical. Most components will be mixed within 60 to 90 seconds. Proper mixing ensures complete reaction of the material and prevents any curing issues. Mixing can be completed by utilizing a drill with a mixing blade or a mortar mixer.
Mortar-based Polymer Flooring
Mortar-based systems are typically an eighth inch to one-quarter inch systems that incorporate a polymer resin filled with an aggregate. There are many different options from liquid rich systems that are self-priming or self-levelling to trowelled systems that require a primer.
Self-priming systems are typically installed using a rake or a notched trowel and rolled with a spike roller to level them. Some systems are broadcast with an aggregate to build strength and to create a textured finish. The size of the aggregate will determine the texture of the finish.
Primed systems use a primer layer with the mortar trowelled into it wet-on-wet. Small areas are finished using a hand trowel. Large areas will achieve proper thickness of material by using a screed box and power trowel. Once the mortar is allowed to cure, preparation is completed to remove any imperfections and the area is coated with coatings or sealers.
Decorative Polymer Flooring
Decorative broadcast systems are typically thinner systems: one-sixteenth to an eighth inch. These can utilize decorative quartz aggregate or decorative flakes in a range of sizes. Most systems use a primer layer that incorporates a broadcast to build thickness and make a more uniform finished colour. The primer is applied with a squeegee and rolled with nap rollers. Excess aggregate is removed and the undercoat layer is applied in the same manner as the primer and broadcast again. Sealers are then applied. Depending on the system and the finish desired, there may be multiple layers of sealer.
Self-levelling or High-build Flooring Systems
Self-levelling flooring systems or high-build flooring systems can range from 25 to 30 mils up to three millimetres. They are typically smooth with a glass-like finish. After proper preparation, the floor will be primed to seal off the substrate to prevent any outgassing in the concrete and pinholes or bubbles in the system. The self-levelling or high-build system is then installed using a notched squeegee or rake to apply to the proper thickness and allowed to cure.
Kyle Tierney is director of technical service at Stonhard, a leader in manufacturing and installing high-performance epoxy and urethane floors, walls and linings. Kyle is a seasoned professional in the field of polymer floors who has been a driving force behind the technical development of products since he began his career with Stonhard as a product engineer in 2004.