Preserving outdoor wood furniture is vital to extending the life of the products. Unlike plastic or metal, wood items are especially susceptible to moisture, sunlight and cold weather. It is recommended that you bring the furniture indoors during the winter months and cover it when not in use. To preserve wood finish, you should treat the wood regularly.
Start out with the best outdoor woods. Not every wood is made for the wear and tear of outdoor weather. Pine and red oak, for example, are just not made to handle the elements. Redwood, cypress and cedar are recommended for their natural ability to repel bugs. White oak and black locust are recommended for their ability to repel moisture. Teak and mahogany are also excellent tropical woods for outdoor use.
Bring it indoors. If you live in a climate with cold, rainy or snowy winter months, you should bring any wood furniture indoors into a garage or shed during winter if possible. At the very least, pull the furniture beneath a patio covering or overhang that offers some protection.
Cover your furniture properly. You should pull the cover tightly over every piece of furniture and then tuck it underneath the legs of all the chairs and tables to make sure moisture doesn't saturate into them. Not all covers are alike, either. The Wall Street Journal recently rated Brookstone's outdoor furniture covers as the best overall covers and the best value. The heavy-gauge covers are reinforced with tear-resistant vinyl and have a flannel lining to help protect against surface scratches.
Treat the wood regularly. Use high quality wood stain, oil, sealer or paint every one to three years to keep the furniture preserved and looking fresh. Depending on the type of wood furniture you have (redwood, teak, cedar, pine, oak), you are going to have to treat it differently. Inquire at your local hardwood store about the correct wood treatment to use for your type of wood.
MarthaStewart.com recommends that you first give the furniture a deep cleaning with a soft-bristle brush and powdered-oxygen bleach. Sand off any stains as well as any existing finish. For stained wood, apply a stain that contains a water-repellent preservative or apply a sealant after it is dry. For paint, make sure all the old paint has been removed before applying a new coat or staining.
Make sure to keep your wood furniture free of standing water. Don't leave pieces standing in water or let chairs fill with water during a rain.