Paints and Coatings: Match Substrate and Surface
May 27, 2011
This is Chris Matt, Managing Editor — Print & E-Media with Maintenance Solutions magazine. Today's tip is matching the right substrate to the proper surface.
The type of surface and condition determine the best paint and coatings option. Is the surface concrete or masonry? Wood? Drywall? Metal? Is the surface bare? Is it previously painted? Is the project a touch-up involving color-matching?
The key to ensuring an effective match between the paint and the substrate is understanding label and material safety data sheet information, which is available from the vendor. The paint must protect the substrate while meeting a facility's need for proper air quality and sustainability. Products with high pigment percentages are more costly but offer greater surface protection and better hiding qualities.
Managers might have other objectives, though. For example, with the emphasis on energy efficiency, the goal might be to use paint with a ceramic additive, which provides insulation by adding an invisible, radiant-heat-reflecting barrier. For a high-visibility reception area, managers might need to specify a surfactant to reduce surface tension and smooth out brush marks.
New rheology modifier additives that are free of volatile organic compounds are formulated to improve pigment dispersal, provide good leveling, and resist sagging. They also prevent misting and paint scatter during application.
Biocides — preservatives and fungicides — are additives to latex paints used for exterior or high-moisture interior applications. Manufacturers add defoamers to prevent air entrapment so the surface is free of pinholes. They also are developing multi-tasking additives, such as defoaming-coalescing agents.
Matching the texture of the surface to be painted requires using the same application method — brush, spray or roller — as used originally. Another technique is using clear spray-on sand or orange-peel coating before applying the final coat.