Deck Oil

Deck oil is a penetrating wood finish specifically formulated for exterior wood surfaces such as decks, terraces, outdoor furniture, and fences. Unlike surface-forming finishes (paints and varnishes) that sit on top of the wood, oil penetrates into the wood fibers, providing protection from within. This makes it ideal for horizontal surfaces subject to foot traffic and pooling water, as there is no film to crack, peel, or blister.

Deck oil protects wood in several ways: it repels water, which reduces swelling, shrinking, and the cracking that results from moisture cycling; it blocks UV radiation, which causes the wood to gray and deteriorate; and it nourishes the wood fibers, keeping them flexible and resistant to surface checking. Most deck oils also contain fungicidal and anti-mold agents to prevent biological growth.

For best results, deck oiling should be performed annually or every other year, depending on the exposure and wear the deck receives. The ideal time is late spring or early summer during dry, warm weather (above 15 degrees Celsius) when the wood is completely dry. Before oiling, the deck must be thoroughly cleaned to remove dirt, moss, algae, and remnants of old oil. Power washing followed by a few days of drying produces the best surface for oil absorption.

Apply the oil with a roller, brush, or pad, working with the grain and maintaining a wet edge to avoid lap marks. Two thin coats are better than one thick coat — the first coat soaks in deeply, and the second coat provides additional surface protection. Excess oil that has not penetrated after 15 to 20 minutes should be wiped off to prevent a sticky, dirt-attracting surface.