When we moved into our rental apartment, everything was freshly scrubbed and painted and bright and lovely. Problem is, two months later the place still smells of paint fumes and VOCs (volatile organic compounds), no matter how often I open the windows! With a baby on the way, the quality of the air in my home is more important than ever, yet that old VOC-laden paint was already there before I had a say so.
Traditional paints can continue to release VOCs for years, and if you’re trying to improve the air quality inside your home, it may not be as simple as just applying a fresh coat of low-VOC paint. Water-based paints are designed to be breathable, so while low-VOC paints do offer some measure of protection, they won’t completely seal off the VOCs coming from the coatings underneath.
When trying to upgrade an existing home to low or zero VOC paint, you have three choices:
Paint Over It: If your previous paint job is more than 5 years old, you may choose to just paint over it with low or zero VOC paint. How long paint releases VOCs depends on the type of paint, the surface being painted, and the climate. It’s generally thought to be strongest during the initial drying and curing, then to continue for several years and possibly even (in small amounts) for the life of the paint. However, if the previous coating is pretty old, the amount of off gassing is likely to be pretty low, and at least you’ll be making a nontoxic investment for the future.
Remove Old Paint: The only way to stop off gassing completely and forever is to eliminate the source. If you’re ambitious, you can sand or strip away the old paint coatings to give you a fresh surface for your low VOC paint. Keep in mind, however, that the old paint may contain lead; or be covering manufactured materials, such as particleboard, which often contain hazardous chemicals like formaldehyde, that produce VOCs as well. So sanding old paint down to the bare material may not really help reduce VOCs, and could even make matters worse.
Some people prefer to completely remove old coatings of lead-based paint, so that you never have to worry about the paint chipping and uncovering the old layer in the future. However, lead-based paint removal shouldn’t be done casually by homeowners, due to the risk of lead exposure from the dust and fumes. Consider hiring a contractor who specializes in lead-based paint removal, and be sure to check out our article on the Dangers of Lead Paint in Your Home.
Use a Sealing Primer: A third option is to paint the surface with a non-toxic, sealing primer, such as AFM SafecoatHard Seal (for nonporous surfaces) or Safe Seal (for porous surfaces). These products are very effective at blocking VOCs, including formaldehyde, from old paints and building materials. And although they’re a little pricey, these sealers may be just the solution in situations like mine, where the toxic paint is pretty fresh, and there’s no feasible way to remove it.
Try to do your painting during dry seasons, such as fall and winter, and consider using a dehumidifier to speed up the curing process. The drier the air, the faster VOCs will be drawn out of the paint, which you can then remove from your home by running fans and opening windows.