A while back I painted the trim on the outside of my parents home. I noticed that the only sign of decay, was where the joints intercepted. This is the only place that these weather exposed boards had signs of problems. The most likely place that water and moisture of the exposure to the elements could be accumulated and making slow evaporation. If boxes are stacked on top of one another with unprotected edges, allowing a place for moisture to build and start problems from the outside, have to be susceptible to the same circumstances as the trim? The inside joints of the trim, had never been painted allowing moisture to build and was obvious in the rotted spots, which was moist and spongy. I will not put a box out without painting the edges. I have not had a problem separating my boxes even stacked 4 deep heavily laden, at least no more than boxes glued on the inside by propolis. However, will say, I try to keep at least 10 to 15 boxes assembled and stocked with frames, ready to be used at a minutes notice. I have noticed my warehoused, preassembled boxes stacked in this manner, sometime need to be ''slightly'' bumped with a rubber mallet to separate them, which is easy enough, and, I have the comfort knowing that I have done all I can to insure that these boxes should last years longer than boxes with unprotected edges. Again, that is my take, experience, and opinion.
Kamon Reynolds of Tennessee's Bees. Has a video of hot wax dipping his boxes and explains the benefits and process of this practice. I am very interested in what he is doing, and perhaps looking to try this sometime in the future.
Phillip