Acrylic Enamels for Wooden Decks
Last week, we explored the wonders of the ultraviolet spectrum. As we pointed out, although our bodies need UV light to make Vitamin D, in general UV light is bad news for outdoor structures. UV radiation fades colors and ages materials, especially wood. That’s why PennCoat recommends you use acrylic enamel paints instead of stains on wooden decks. The enamel is a much better defender against UV rays, and it has the additional benefit of not needing to be reapplied every other year.
Acrylic Floor Enamel
One of our favorite commercial paints for exterior wood is Acrylic Floor Enamel. It made of 100 percent acrylic resin, with titanium dioxide and extender pigments. We’ve discussed acrylic resin in previous blogs, but as a reminder, the material is water-borne in the can but dries to a water-resistant film. The resins are derived from methacrylic and acrylic acids or related compounds. The chemical properties of acrylic resin make it highly resistant to weather damage and UV rays that can cause yellowing, cracking and crumbling.
Acrylic Floor Enamel has good moisture resistance and very good adhesion. It’s also LEED-certified and has a low amount of volatile organic compounds (VOCs), about 0.42 pounds per gallon. The enamel is 40 percent solid by volume and 54 percent solid by weight. Its density is 10.71 pounds per gallon. It does not have a flash point and an unopened can has a minimum shelf life of one year.
To prepare a wooden deck, first sand the surface smooth and remove the sanding dust. The surface must be free sound, clean, dry and free of dirt, grease, oil, mildew and other foreign substances. The product is self-priming, and you’ll want to apply two coats. The base color is white, by you can mix in any tints you wish. Mix thoroughly before use. You should not apply the paint when the temperature is outside the range of 50°F to 90°F, or if rain is expected in the next 48 hours. You could apply it with an airless sprayer set at 2,000 psi and equipped with a tip in the 015” – .019” range. However, it’s probably simpler to use a brush or roller. No thinning is required.
You can expect a gallon to cover about 350 to 400 square feet. The film thickness should be 4.0 to 4.6 mils wet and 1.6 to 1.8 mils dry. After applying the first coat, allow to dry at least eight hours, but longer if the temperature or humidity are high. Apply a second coat, and then clean up your tools with soap and warm water. The deck should be ready for light foot traffic in about 24 hours.
While not a particularly dangerous product, it can irritate your eyes, skin and respiratory tract, so gloves, eye protection and a nose mask are good precautions. Simply wash away any paint that gets on your skin, and if necessary, flush your eyes for 15 minutes with water. Tints contain ethylene glycol, which is dangerous if ingested. Even though the product has low VOCs, it’s a good idea not to breathe in the vapors. Ventilation is usually not a problem when painting an outside deck, but if you paint interior surfaces, make sure the area is well ventilated.