Deck Maintenance

  • Wood should be periodically cleaned to remove fallen leaves, dirt and other debris from its surfaces. There are a variety of methods for cleaning your deck and products you can buy for this purpose. Using detergent (or bleach), water and scrub brushes works well, as does power washing your deck. If a power washer is used, be aware that it can damage the wood if it is held too close to its surface. If you’re unfamiliar with how to use one, consider calling on a professional.
  • Be especially careful to remove debris that collects between boards. There are special tools available for this. But, regardless of the tool used, the important thing is that the dirt is removed. Fallen leaves can stain a deck and collect moisture, leading to mold and mildew problems. The deck should be regularly swept to remove them.
  • One of the major reasons decks need to be replaced is dry rot. Dry rot is a fungus that feeds on wood, leading to its rapid deterioration. Once dry rot has established itself, it often leads to further infestation of the wood by termites. The combination can quickly destroy a deck, and also provides a pathway into the wooden structures of the rest of your home.
  • Since dry rot requires wet wood to feed on, this problem can be avoided by sealing wood off from moisture. It’s also important to keep the deck free from debris and dirt build-up between boards where moisture collects and dry rot can start.
  • In general, it’s a good idea to treat your deck the same as you would any other flooring surface in your home. Cleaning and inspecting it regularly will greatly minimize the need for major repairs.
  • Other tips for keeping your deck clean include using a stain remover to remove stains, sanding splinters down, and using pot feet for planters so that they don’t stain the deck. For decks built close to the ground it’s a good idea to spread a polyethylene barrier over the soil, and then cover this with decorative rock. This will help to keep moisture from seeping in from underneath the deck.

Sealing to protect against water and UV rays

  • If your deck is newly built, it should be allowed to weather for one year before a sealant is added. This ensures that the wood can dry out and the fibers can open so that they will be able to soak in the protective sealant. To assist this weathering process the new wood should be treated with a new wood treatment. A new wood treatment will provide protection from sun and rain and allow the wood to weatherize for its first year.
  • When applying protective sealant, it’s important to prepare the deck first. Clean the deck to remove dirt, debris and dry rot. Then, remove any old paint or sealant and sand the wood to remove rough spots and splinters. The most important part of re-sealing your deck is to start with a fresh surface of exposed wood that is able to absorb the new sealant. The deck should be completely dry before sealant is applied: wait a minimum of 2-3 days after cleaning to allow for this. If the wood is not dry, the sealant will not absorb properly. Read and follow the instructions on the product label carefully when applying sealant. Be sure you choose a product that will serve your needs.
  • A clear sealant lets the natural beauty of the wood show through, but won’t provide the same UV protection as a pigmented finish. For this reason, a clear sealant needs to be reapplied every 12 to 18 months, while a pigmented one can last for up to three years. The sealant should protect your wood against both moisture and sun damage.


  • Paint can also be applied to your deck, but will not provide the same degree of protection as a wood sealant. If paint is used it’s best to use it for only the railings and balusters as it will not stand up well under foot traffic.

Environmental costs of poor deck maintenance

  • In addition to a financial cost to the homeowner, there is also an environmental cost of poor deck maintenance. Each year about 3 million new decks are built in the United States. Every year an additional 3 million decks are replaced or repaired due largely to poor maintenance. This wasteful use of lumber contributes to the depletion of our nation’s forests, and the unnecessary loss of an important ecological resource. The average acre of forest yields only enough wood for two or three decks to be replaced each year. But, with a little maintenance and care, the average deck can easily last several decades. If all decks in the U.S. were cared for properly, it would save over 6 million trees from being cut in one ten year span.

Deck Repair

  • In addition to regularly cleaning and resealing, your deck should be inspected for any damage that needs to be repaired. Loose nails or boards should be secured, and boards with dry rot damage should be replaced.

Inspecting For Damage

  • If damage has occurred, your first step is to determine the extent and cause of the damage. If dry rot or water damage has occurred, be sure you find the source of the problem so that it can be fixed. Look for drainage issues and clear out any clogged drain pipes or other irrigation problems. Check posts, beams, and joists that are at or close to the ground because they are especially likely to suffer damage.

Maintenance Tip

  • Check, then clean deck surfaces every couple months to remove dead leaves and other litter that could promote moisture retention and promote dry rot and mold. Be especially vigilant about cleaning between boards. If your deck is close to the ground, putting a polyethylene sheet below the deck can reduce moisture in the deck itself, however, make sure it runs off so water doesn’t pool.

Cleaning The Deck

  • There are a number of deck cleaners available. Find the right one for your deck construction.
  • If deck cleaner alone doesn’t quite do the job, use a pressure washer. Keep the tip 4–6 inches away from the deck’s surface and use less than 1000 psi (pounds per square inch). Too close with too much pressure and you could damage the wood. Use short, sweeping motions and move smoothly across the surface to get a consistently cleaned surface.

Remove and repair damaged areas

  • Use a screwdriver or awl to test places where the wood looks like it might have dry rot. If the wood is soft, it should be replaced, otherwise the piece can be saved. Dry rot is a fungus that spreads through wet wood. If you have a dry rot problem, it is essential that all affected boards are removed and disposed of in such a way that other timber does not become infected.
  • Use a screwdriver or nail puller to remove screws or nails. If screws are rusty and hard to budge, the boards can also be pried up.
  • Weather-damaged boards sometimes twist out of shape, popping nails and creating an uneven walking surface. These boards can often be fixed rather than replaced. To create a simple tool for this purpose, cut a wide notch out of a 2×4 so that it can be slipped over the end of a twisted board and used to move the board back into place. Once the board is in place, 5” deck screws can be used to secure the board down firmly.
  • When new boards are needed to replace damaged sections of the deck, it’s a good idea to use a biodegradable cleaner and brightening agent on the older portions of the deck so that the new and old parts of the deck more closely match. A sealer should also be used to finish off the deck and guard against moisture..

Fix popped nails

  • When wood shrinks and expands in weather, it can cause nails to pop up out of the boards. The best way to fix these is to replace the nails with longer, thicker nails that will have a better hold. A drift punch can also be used to countersink the nails into the wood. You can also replace nails with galvanized deck screws.

Modifications and improvements

  • Decks come in many styles and can be modified relatively easily to fit your changing needs. A single deck can be converted to a multi-level deck, or a basic rectangular deck can be changed to an L-shaped, wrap-around style. Other alterations include adding accessories such as gazebos, planters, or built-in seats. If your deck overlooks a shoreline or other windy areas, your railing can be converted into a windbreak by using framed glass panels to enclose your deck. Stairs, or wheelchair ramps, can also be added to decks to aid in accessibility.
  • When making modifications or repairs build to the specifications and instruction found in the prescriptive residential wood deck construction guide 2012