With a little maintenance, a wood deck will last many years. In areas where snow and heavy rains are common (such as in Chicago, Minneapolis, or Denver) cleaning and sealing the deck is extra-important to extend the deck’s useful life. A local carpenter can provide suggestions you should know for your region of the country.

Cleaning

Whether you plan to seal the wood or not, a careful cleaning of your wood deck before winter will preserve its natural beauty. Mildew, dirt and other foreign objects tend to discolor wood over time. A pressure washer will clean a wood deck much faster than scrubbing with a broom. However, you must learn the right way to pressure wash so it doesn't do any damage. Test the pressure washer at 500-650 psi on an inconspicuous part of the deck, increasing the pressure gradually. Be sure to hold the nozzle at a consistent distance from the deck (12 inches is recommended), cleaning with an even sweeping motion. 

To remove staining, use an eco-friendly cleaning solution. Moisten the deck and sprinkle with baking soda. Let sit one hour; then rinse. Oxygen bleach is another cleaning option. Unlike chlorine bleach, oxygen bleach does not contain harsh chemicals like sodium hypochlorite. Rather, it is made of sodium percarbonate, a powdered form of hydrogen peroxide. Powdered bleach is made when hydrogen peroxide is added to natural soda ash or natural borax. The advantage of oxygen bleach is that it cleans stubborn stains without harsh, potentially harmful, chemicals.

Staining and Sealing

If any boards are damaged or rotted, replace them before staining and sealing the deck. Hire a carpenter if you are not sure of how to do this properly. Hammer any nails that have popped up or loosened. If the color is still fresh looking you won’t need to stain.

To test whether you need to seal the deck, drop water on boards in different areas of your deck. If water beads, you won’t need to seal. However, if the liquid soaks into the boards, apply a sealer.

Sealers are available in clear and pre-tinted varieties. Apply the sealer with a sprayer, roller or wide brush, allowing the liquid to soak into the wood.

Winterizing your wood deck will maintain its beauty and function. A professional carpenter in your area can help you replace any damaged components and recommend the right cleaning and sealing products to use.

Updated September 17, 2018.