On Tue, 05 Jul 2016 08:22:14 -0700, rhonda.hodas.hack wrote:

So - the answer, for a barely even novice,
looking for both a non-toxic, waterproof sealer which protects against
mildew, UV, etc... would be...?

When you find one, let us know :-).

Seriously, I don't think the "perfect" exterior finish exists. None last
for more than a few years and most only 1-2 years. If you believe the
statement that all finishes are non-toxic when cured, you could try
marine epoxy over shellac (SealCoat).

If you're keeping the birdhouses, my suggestion is pure tung oil,
reapplied every year. See:

https://www.dutchcrafters.com/Wood-F...ng-Oil/p/11419



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