Beekeeping 101 - Protective Coatings For The Hive
Some wood may last longer while some may last much less depending on the climate, but hives are definitely helped by some type of protective coating. The average life of a bee box is about seven years. Scraped and routinely painted, equipment can go much longer. The problem is with film coatings. Since the inside surfaces of bee hives should not be painted, the paint film on the outer surface is stressed by water migrating to the film from the "inside" of the hive rather than the outside of the hive. Oil-based paints are the worst and will readily peel within just a couple of years. Due to ease of application and lower cost, latex paints are common choices. The rubber-based latex paints will flex and resist chalking and peeling much more than oil paints, but they will finally succumb to mildew and peeling.
Some commercial beekeepers and beekeepers in other countries routinely dip equipment in paraffin or beeswax. This is a good finish that protects the wood from all sides and ends, but requires working around hot, flammable paraffin. Once the paraffin has begun to show signs of wear, simply dip it again in hot paraffin to recoat the finish and to remove wax and propolis residue. In recent years, polyurethane exterior stains have become popular and have been consistently improved. As with paraffin impregnation, many of these stains are water repellant, resist mildew and fading and clean up with water and soap.
A final warning has to do with pressure treated wood that is now in universal use. The materials used to preserve the wood are usually toxic to honey bees. Thus, this wood is not recommended for bee colonies. Even the sawdust from this wood is considered a health hazard and dust masks are recommended when working so-called "Wolmanized" treated wood.