We are trying to decide what what to seal our plywood on the inside of henhouse with? Curious what others have used or if you seal at all? Seem's the wood wouldn't last as long after cleanings with water etc. Also concerned about toxic products. Let us know your thoughts!
Putting a protective coating on the wood will make it last longer and make it significantly easier to clean. Poo has a tendency to stick REALLY HARD to bare wood and will require scraping, yet will wipe away with spritzed water if the surface is painted.
I painted the plywood interior on my coop. Two coats of oil-based primer and 3 coats of exterior semi-gloss. Walls and floor. If you prefer the natural wood look, I recommend linseed oil mixed 50/50 with mineral spirits. The oil will give is some waterproofing while the spirits will help it absorb into the wood. It's probably a little high on the toxic level, but would be dry and odor free within a day or so.