The "best" product depends on where the wood will be used. For outdoor wood exposed to weather, use a penetrating exterior sealer or stain. For indoor furniture, a natural penetrating oil or polyurethane is ideal. For food-contact items, use a food-safe mineral oil or beeswax.
Sealing raw wood protects it from moisture, stains, and wear. The process requires three steps: sanding the raw wood smooth, applying a sealer like polycrylic, polyurethane, or oil, and lightly sanding between coats.
The best wood treatment to prevent rot depends on your project, but the top professional-grade choices are penetrating Borate treatments for above-ground use and Copper-based preservatives for wood in direct soil contact. Both penetrate the wood fibers to stop decay fungi and insects at the cellular level.
Untreated wood left outside will naturally patinate over time to become silver-grey in colour. To preserve or intensify the original golden-brown colour, the wood can be regularly treated with oil. The oil is designed to protect the wood.
The "best" oil for raw wood depends on its use. For fine furniture, use Pure Tung Oil for a rich, water-resistant finish. For floors and high-traffic pieces, use hardwax oils like Osmo Polyx-Oil to combine durability with a natural look. For kitchen items, opt for food-safe Watco Butcher Block Oil.
No, you should not use WD-40 to seal wood. It is a petroleum-based penetrant and lubricant, not a wood sealer. Using it on wood will leave a greasy residue that never truly dries, attract dirt, seep into the wood grain, and permanently damage or ruin future paint or stain jobs.
Another benefit is that polyurethane keeps moisture away from wooden surfaces to prevent rot.
The most durable wood finish depends on your project. Epoxy is the hardest and most waterproof for tabletops, 2K Conversion Varnish is the industry standard for commercial furniture, Polyurethane offers the best DIY balance of scratch resistance for heavy-use items, and Spar Varnish handles exterior weather.
Coal-tar creosote
Creosote was the first wood preservative to gain industrial importance more than 150 years ago and it is still widely used today for protection of industrial timber components where long service life is essential.
Yes, you can absolutely treat untreated wood yourself. For effective DIY protection against moisture, rot, and insects, choose from either chemical or natural treatments. The specific method depends on whether the wood will be used indoors or outdoors.
The jar of petroleum jelly or Vaseline that you have in your medicine cabinet can work wonders to remove white water rings from furniture. The oily petroleum base penetrates the finish on the wood, displacing the moisture trapped inside, and the oils also nourish and condition dry wood.
Oil penetrates the wood fibers to enhance the natural grain and protect from the inside out. Wax sits on the surface, providing water resistance and a soft sheen. For best results, use a combination: apply oil first to nourish the wood, followed by wax to seal it.
If sanding feels like too much effort, there's another way. Start by brushing off debris and cleaning the wood with a gentle cleaner. Once dry, apply a wood restorer to revive the colour and fill minor imperfections. It's an easy, effective approach that's kind to the existing finish.
Waterproofing untreated wood involves cleaning the surface, sanding it smooth, and applying a protective finish. You can use penetrating oils (like tung or linseed oil) for a natural look, synthetic sealers (like polyurethane) for durability, or waterproofing creams for long-lasting exterior protection.
Motor oil repels water and deters insects, effectively slowing down rot in outdoor wood, such as fence posts or barns. However, it is an unregulated, environmentally hazardous practice. It never fully dries, leaches into the soil, emits a strong odor, and poses toxicity risks.
The best natural wood sealer depends on your project. For fine indoor furniture and floors, Osmo Polyx Oil (a hardwax oil) is top-rated. For outdoor decks and fences, Ready Seal Exterior Wood Stain and Sealer provides exceptional UV protection and weather resistance. For food-contact items, pure Tung Oil or Mineral Oil is ideal.
The "longest-lasting" top coat depends entirely on your project. Here are the top-performing, durable options categorized by your specific needs:
Permanently waterproof
The advantages of a polyurethane coating cannot be denied. The most important advantage is the permanent impermeability it gives to the fabrics. Unlike a conventional impregnation or a DWR, a PU coating is resistant for a long time.
Whether a material is "better" than polyurethane depends entirely on your project's needs. Polyurethane is unmatched for heavy-duty, budget-friendly scratch and water resistance, but alternatives excel when you need better UV protection, easier repairs, faster drying times, or a more natural feel.
The cheapest way to waterproof wood is by using repurposed natural oils (like mineral oil) or repurposed used motor oil. For a natural, food-safe option, a mix of beeswax and mineral oil is highly affordable. These methods cost just pennies on the dollar compared to store-bought sealers.
Polyurethane is not made for outdoor use. The first and most important reason is that most polyurethanes are designed for indoor use. They aren't formulated to withstand UV rays, varying temperatures, or constant moisture. Outdoor elements quickly break down the finish, causing it to crack, peel, and flake.
Oiling wood seals it by penetrating the fibers and hardening as it cures, creating a water-resistant barrier that protects against drying, cracking, and spills. The best oil depends on your project—choose natural drying oils (like tung or linseed) for furniture, mineral oil for food surfaces, or specialized blends for outdoors.
Bleach and Ammonia-Based Cleaners
Using these cleaners may discolor wood, erode the finish, and damage deeper layers of your floors. “Avoid harsh chemicals or abrasive cleaners, such as ammonia or bleach, which can strip the finish and damage the wood,” says Scott.
While WD-40 is a great multipurpose solvent, it is a poor long-term lubricant and should never be used on items that require specialized lubricants, come into contact with food, or are made of sensitive plastics and rubber.