Concrete/cement is the No. 1 building material in the world – and one the most problematic surfaces you’re likely to encounter in typical commercial work, says Gary Vorick, Global Training Manager, Sherwin-Williams.
Here’s what you need to know to prevent paint failure on concrete and masonry substrates.
Moisture, movement and a variable surface
Unlike steel, concrete is not always a homogenous surface, Vorick says, and tensile strength is very weak compared to steel.
“The surface can change from one side of the room to the other, and moisture is always going to be a concern,” he says. “There is going to be movement, which means there will be cracks and expansion joints to be filled.”
Before topcoating, you may need to check for bug holes or grind the surface smooth.
Different approach, depending on substrate type
You also need to consider the type of concrete you’re coating – poured wall, concrete block, slab, etc. – as each must be dealt with differently.
Other factors to consider
Is the surface above grade or below grade? Is there any immersion? Finally, how aggressive will the environment be on the coating?
“Schools are subject to much more aggressive wear than, say, an office building,” Vorick says. “And if you’re coating a floor, add in the abrasion factor.”
Best coating choices
Sherwin-Williams’ line of Loxon® exterior concrete and masonry coatings is the perfect place to start.
From surface conditioners to primers to finishes and clear water repellants, Loxon products offer commercial contractors everything they need for most concrete coating jobs.
For extremely corrosive or immersion environments, Vorick recommends the high-performance epoxies and urethanes produced by the Sherwin-Williams Protective & Marine division. See your sales rep for recommendations.
Take extra time upfront to carefully evaluate substrate surfaces – and their overall condition – before you apply a new coating.
Tap into your Sherwin-Williams sales rep’s expertise. He or she will be happy to arrange a site visit to help you determine the exact right prep methods and coatings to ensure your job is a success.
Finally, you can go online to get more information on painting concrete on the Sherwin-Williams contractor website.
This article was originally published in the Spring 2017 issue of the Sherwin-Williams CommercialPro newsletter. Get more business-building tips and info on products, services, discounts and project solutions on the Sherwin-Williams contractor website