1. Beginning
Concrete floors can be made either mechanically or chemically. Both forms of preparation aims to remove the top layer of concrete; removing contamination and providing a surface profile for the coating to bond to. The ‘FeRFA’ Resin Flooring Association recommends preparation is completed in a mechanical fashion. Mechanical preparation reduces the risk of additional contamination if the acid is not washed away correctly, and provides a better surface profile. Mechanical preparation can be carried out by grinding or shot blasting.
2. Potential Problems
Several different factors that should be considered prior to the application of a floor paint; namely the composition of the concrete, the amount of time it has been installed and its overall strength of the material. Anhydrite screeds are not suitable to receive a floor coating due to poor tensile strength; new concrete screeds should be coated many times with coatings with a water base to prevent blistering and the concrete should have a minimum compressive strength of 25N/mm2.
3. Products
The majority of single part floor paints are not suitable for application on garage floors as they suffer from ‘hot tyre picking’. Where a floor is subject to wheeled traffic, FeRFA recommends expoxy floor paints with two parts. Water based epoxy floor paints are suitable for light traffic including occasional vehicle traffic. Whereas high build epoxy floor paints are recommended in areas subject to regular traffic.
4. Application
Care should be taken of the pot life of epoxy floor paints. Due to the chemical reaction which occurs when the two parts are mixed together, the pot life is significantly shorter than other paints. Care should be taken to have the area to be treated ready for application before mixing. Applicators should make sure that there is enough labour to apply a whole unti within 20 minutes of mixing.
5. Curing Times
Epoxy floor paints cure to a tack free state in one day at 20 degrees celsius and are ready for wheeled trafficking after 2 days. Curing times will be reduced or extended in negative correlation with temperature. For example, at 10oC the curing time will twice as long. Applicators should consider the ground temperature is often more than 5oC less than the room temperature.