All professional grade stains we use possess sealers within the stain. The oil-based stain we use is our own formula which is a true oil-based stain, containing both fast and slow-drying oils for maximum protection. This oil-based stain soaks in and seals from within. After staining with this stain, the wood is protected from UV damage and water intrusion, and in fact, just moments after using this product, water beads up on the wood.
In those instances where we have no choice but to use a water-based stain, we use Sherwin Williams SuperDeck semi-solid or solid stain. It too has its own sealant in it, and has significant water intrusion protection and UV damage protection.
Sealants by themselves, are film-forming water-based products that tend to crack and peel over time and lose their protective capacity very suddenly. Clear sealant’s UV protection is very low as well. Some of the other thicker sealants (elastomer-based) seal in the deck’s natural moisture and don’t allow the wood to breathe. This, in turn, causes premature rot under the coating.