To retain the wood’s natural color, you need to seal your deck yearly. Here’s how to choose a sealant.
Conventional sealers: Most mainstream home improvement stores sell oil- and water-based polyurethane. Oil-based polyurethanes contain high levels of toxic volatile organic compounds (VOCs) that compromise indoor air quality. Water-based products have far fewer VOCs, but they also use petrochemical additives (such as hardeners) that contribute to environmental pollution.
Healthier alternatives: Plant-oil preservatives such as tung and linseed oil are also effective and healthy. These must be applied to the deck once a year to be effective.
Au Naturel: A deck made of certified sustainable hardwood can last decades longer than one built with softer, sappier wood–even with no sealant or stain put on it.