Commercial Painting – How To Paint CMU, Masonry, and other Structural Block
Block walls, brick, masonry, CMU, and other type of structural block can often bee challenging to paint. It’s porous, rigid, and highly profiled, creating unique challenges that require specialized coatings, and proper equipment to ensure that the material is adhering to the surface. Additionally, block is stationed outdoors, so in most cases, not only are you dealing with the rigid substrate, but you’re also dealing with the difficult weather conditions that exterior coatings are exposed to.
Commercial Painting Equipment
When rolling paint, the important thing to look for is which type of roller to use. And the selection is ultimately decided by the surface. If you have a smooth surface like drywall, then you’ll want to go with a 1/4″ nap roller. A nap this small will allow you to apply a smooth coat of material over the surface, without leaving a n orange peel finish. So, when dealing with masonry, you’ll want to choose a 3/4″ nap roller. A 3/4″ nap roller has enough absorption to hold more material, and allow you to work the material (paint) into the cracks and crevices that are prevalent on the porous and pitted surface of the brick.
Commercial Painting Masonry Paint
Now that you know what roller you’re going to use, now you need to figure out which paint to use. And as always, this will be decided based off your substrate and your environment. The substrate is extremely rigid and porous. So you’re going to want something that has more viscosity than typical acrylic paint. Sherwin Williams Block Filler is a great product for masonry priming. It has the viscosity and “beef” to fill in the pores and level out the rigid valleys and crevices on the substrate. But be sure to read the TDS. This block filler requires more than 1 coat of paint. The DTF (dry film thickness) is 8 mils. Which is about 2-3 coats of material. So don’t apply 1 coat and stop there.
Once that masonry is “block filled,” you can then apply your top coat. This is when you’ll need to assess the environment. Is area interior or exterior? Is it cleaned? What type of chemicals and cleaners are applied to it? How much sun exposure does the are receive? Will there be sitting water (snow)? All of these are important questions to ask. If indoors, Then you can consider an alkyd paint. Alkyd’s are beneficial because of their superior adhesion and they create a harder shell. But if they get sun exposure, they can amber and yellow, so you’d want to avoid using them outdoors.
If the block is outdoors, then you’ll want to go with a water-based paint, like an acrylic or latex. Water based paints can tolerate sun-exposure, and won’t fade of break down due to UV rays.
Overall, your decision to paint brick, masonry, CMU, or architectural block is a good one. But just make sure if you decide to paint it, that you’re using the appropriate equipment, and the appropriate material.
PennCoat, Inc. has been providing industrial painting, commercial painting, epoxy flooring, and polished concrete services for nearly 30 years. Our experienced installers are trained and equipped with the proper knowledge and tools to ensure that every installation is installed efficiently and safely. PennCoat, Inc. provides service toPennsylvania,New Jersey, Maryland, and Delaware. And we coverYork,Lancaster,Philadelphia,Chester,Montgomery,Baltimore,Harrisburg,Dauphin,Bucks,Berks, and other counties in the surrounding area.
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