System Three epoxies provide exceptional protection to wood components, in both interior and appropriate exterior applications. However, we do not recommend them for concrete/wood flooring or exterior wood decks. This is mainly because of the difficulty and expense involved in getting an acceptable appearance. Products made specifically for concrete/wood floors are economical and generally easy to apply and provide a good appearance as well. but There are a number of brands available at retail paint and "big box" stores.
Exterior wood decks are best finished with a penetrating oil or stain. Because they penetrate rather than forming a film on top of the wood, the expansion and contraction of the wood will not cause the coating to crack and peel. But they will weather in a short period, so plan to recoat at least once a year.