In South Africa, probably the most durable paint for hives is branded
Everbond. It's UV-resistant and waterproof, and typically used, for
example, to seal joins on roofs and to seal koi ponds, etc. I use it on
untreated wood and it goes on like a disease and maintains a rubbery
kind of texture. Given a choice, I buy woodenware that has been
hot-dipped with creosote. This must be the single best long-term way
to protect bee furniture. CCA treatment is almost as good, but needs
subsequent painting to counter the dryness it infests the wood with. I
also use Everbond to seal jumbo sugar syrup feeders - and it works
like a charm.

Barry Sergeant
Kyalami
South Africa