Wood Sealant

So I'm trying to figure out if I should seal the beehive woodenware or not.  The boxes I built and painted seemed to be in pretty sad shape after one winter, despite using two coats of exterior latex paint.  One article I read claimed that the moisture from the bees during the winter migrates through the wood and causes the paint to peel on the outside.  Seems possible.

However, finding something non-toxic / food-grade is an exercise.  One problem is that I want to paint over the sealer, and not all of them are paintable.  I was considering boiled linseed oil--but then I found out that the commercially available stuff uses metal salts to accelerate drying, and it's really raw linseed, not boiled.  No dice.  An article on natural wood sealers and another on non-toxic paints gave me a list of things to check, but the one I found was via a source I don't remember.

AgraLife makes a couple different products, Lumber-Seal and Hive-Seal.  The former is available at Home Depot and is supposedly food-safe.  The MSDS for Lumber-Seal notes that "All Products except Hive-Seal contain 1% Zinc Oxide/Borate for film protection and are not considered hazardous by EPA."  However, the actual composition is noted as a "trade secret," which makes me somewhat suspect.  What I don't know for sure is if the stuff is paintable or not.  Perhaps it'll say on the can.

Perhaps I'll pick up some Lumber-Seal for the pressure-treated base and hive stand, and do the outside of the woodenware for now.  I could always apply Hive-Seal to the interior when I'm able to obtain it.

Another interesting product I found was Seal-Once Marine Waterproofer, which is paintable.  It doesn't show as food-safe, but if I were sealing a deck or something it appears like a good candidate.  Actually, I might try their Concrete Rust Remover on a couple spots on my driveway and garage floor.

There was one more that intrigued me because it's linseed oil, but there wasn't much info about how it was produced: Earthpaint's "Special Linseed Oil."  It's back to where I originally started looking as far as wood sealers go.  On the other hand, it's twice the price of Lumber-Seal ($66/gal vs $35/gal), plus S&H ($22+ for the gallon container).