How to Clean a Wood Deck Without a Pressure Washer

Regular cleaning not only maintains how your deck looks but also helps prevent long-term damage. To avoid the risk of roughening or even gouging your wood deck, skip the pressure washing in favor of cleaning it by hand. In fact, there are several good reasons to never pressure wash the deck.

Sure, hand cleaning takes more elbow grease. But it’s simple work, a DIY home improvement project that anyone can do, regardless of skill level. Expect to spend two or three hours on the project, not including drying time. Large decks or decks with heavy grime will take longer.

To protect your deck, clean it once or twice yearly as regular maintenance. Cleaning the wood is also the first step in preparation for staining the deck, which also requires stripping away any existing finishes and adding a new sealant. In the meantime, learn how to clean the deck gently, and you’ll preserve its appealing surface longer.

Here’s a step-by-step guide to handling the job without power washing it.

Prepare for Deck Cleaning

Move furniture, plants, grills, rugs, and other items off the deck. Don’t try to work around your belongings. It’s easier to clear everything. You might want to put the items where you can clean them easily once you’ve finished with the deck.

Prepare Homemade Cleaning Solutions

You don’t have to buy special deck cleaning chemicals because many household products work just fine. Here are three homemade cleaning solutions that work gently.

To avoid discoloration and to see which works best, test each wood deck cleaner on a small area before using them on the entire deck. Try not to use anything stronger than what’s needed. Reserve the strongest options for tough stains, such as mold and mildew.

1. Mild Soap Solution

Ingredients:

• 1 gallon of warm water
• 1 cup mild dish soap (without bleach or strong chemicals) or an eco-friendly all-purpose cleaner, such as Simple Green

Instructions:

1. Mix warm water and liquid dish soap in a bucket.
2. Dip a soft-bristle brush into the soapy water and scrub the deck gently.
3. Rinse the deck thoroughly with a garden hose and let the deck air dry completely.

2. Vinegar Solution

Ingredients:

• 1 gallon of warm water
• 1 cup white vinegar

Instructions:

Same as above. Avoid using undiluted vinegar. It might be too harsh for the wood.

3. Baking Soda

Ingredients:

• Baking soda
• Water

Instructions:

1. Mix baking soda with water to create a thick paste.
2. Apply the paste to mildew stains or other spots on the deck.
3. Let it sit for a few minutes, then scrub gently with a soft brush.
4. Rinse the area thoroughly with water and allow the deck to dry.

Baking soda is abrasive, so use it carefully and avoid excessive scrubbing, which could scratch the wood.

If you prefer to use ready-made products but have environmental concerns, look for cleaners bearing the US EPA’s Safer Products label.

Scrub the Wooden Deck the Right Way

Scrubbing a wood deck properly is crucial to maintaining a scratch-free appearance. Here are pointers on the correct technique.

1. Use a Soft Bristle Brush 

The brush mustn’t scratch or mar the wood. Avoid metal and other stiff-bristle brushes. They leave scratches.

2. Wet the Deck

If you wet the deck surface lightly, it will absorb the cleaning solution better than a dry deck.

3. Apply Cleaning Solution

After loading the brush, scrub a small section of the deck at a time. Scrub in the direction of the wood grain to minimize scratches.

4. Scrub Thoroughly

Scrub the wood surface, paying extra attention to stained or heavily soiled areas. Don’t use too much water pressure or hard scrubbing on softer wood types, such as cedar. Don’t allow dirty water to pool or stagnate. Rather, keep the water and solids in motion to prevent them settling into the wood again.

5. Rinse Immediately 

After scrubbing each section, immediately rinse it with clean water using a garden hose. Rinsing promptly prevents the cleaning solution from drying on the wood, which can leave a film, streaks, or water stains.

6. Dry the Deck

Allow the deck to air dry completely before returning the furniture or other items to it.

How to Remove Mold and Mildew

Mold and mildew can be stubborn stains, but there are ways to deal with both: bleach.

Bleaching wood decking is permissible but only if you use oxygen-based bleach. Do not use chlorine bleach intended for laundry. It will damage the wood fibers. Oxygen bleach, like OxiClean laundry detergent, uses sodium percarbonate and hydrogen peroxide as active ingredients. It’s effective against mold and mildew, doesn’t damage the wood fibers, and breaks down into benign elements. Examples of ready-to-used deck cleaners include Restore-A-Deck kits, Defy Wood Deck Cleaner, Gemini Restore Kit, EFC-38.

The cleaners come in powder and liquid concentrates that you mix with water and apply to deck boards using a garden sprayer. After letting the treatment sit for 5 to 10 minutes, scrub the deck. Rinse off the suds and dirt as you scrub.

How to Clean Between the Deck Boards

Removing dirt and debris from between wood deck boards can be difficult, but not if you have the right tools. The best option is to drag a narrow brush or a rigid tool along the length of the gaps as you spray water.

Homemade Gap-Cleaning Tool:

You can make you own cleaning tool by screwing a hook into the end of a broom handle. Or partially sink a few 3-inch drywall screws into a short length of lumber. Space them so they all fit into a gap, then slide the wood piece over the deck boards so that the screw heads dislodge dirt and debris. Follow this up with a plastic bristled brush dipped in cleaner and rinse away the suds and loosened debris.

Specialty Tool

A few companies offer specialized tools for cleaning the gaps between deck boards. They have a thin, flat metal or plastic edge that is hook-shaped. As you drag it through the gaps, it loosens debris, including pine needles and twigs.

Leaf Blower, Vacuum, or Air Compressor

A leaf blower or shop vacuum fitted with a narrow nozzle can blow or suction away loose material but don’t count on either to do a thorough job. An air compressor works better.

Rinse and Dry the Deck

With a spray nozzle attached, use a garden hose to rinse the deck. It might be helpful to redeploy the scrub brush as you rinse to ensure that all the dirt and soap residue is removed.

Apply a deck brightener after cleaning using a garden sprayer or as the manufacturer recommends, then rinse the deck thoroughly. Let the deck surface dry before replacing any outdoor furniture or other items. If you plan to refinish the deck, let it dry for at least two or three days.

FAQs

Different types of decks might require different cleaning methods and routines. Here are some common concerns:

Which Kinds of Wood Require Special Cleaning Considerations?

The most popular wood for decks is pressure-treated fir or pine; both can be cleaned as described above. Cedar and redwood are softer, so be extra careful to prevent gouges and dents. Exotic woods, such as ipe, mahogany, or teak, are harder and tightly grained and thus easier to clean.

Are There Specific Considerations for Older or Weathered Wood Decks? 

Older or weathered wood decks require extra attention to prevent further damage. First, look for signs of decay and replace any deck boards that have splintering, warping, or rot. This is also an excellent time to inspect for deck safety, including examining the fastener connections at the deck’s ledger board, posts, stairs, and railings.

For deep-seated deck stains or build-up due to algae, mildew, or moss, apply a pre-treatment of water and oxygen bleach or a specialized deck cleaner. Apply the solution to the stains, let it sit for a while, and then scrub gently with a soft brush before rinsing.

After cleaning, use a wood brightener to restore the natural color of weathered or gray wood. Most use oxalic acid in combination with other ingredients.

If your deck is significantly weathered or you suspect structural problems, consider hiring a specialist. Or, for better durability, replace the wood deck boards with composite decking.

How Often Should You Clean Your Wood Deck to Prevent Long-term Damage? 

Cleaning is essential to prevent long-term damage to wood decks. How often to clean this outdoor space depends on several factors.

Climate

In moderate climates—neither extremely humid nor excessively dry—cleaning your deck once a year is usually sufficient. Spring or early summer is a good time.

In humid or rainy areas, decks are more susceptible to mold, mildew, and algae growth. In these regions, clean the deck twice a year, once in the spring and again in the fall.

Arid regions don’t usually have mold and mildew problems, but the sun is a threat. It damages wood by drying it out and causing it to crack. The sun’s ultraviolet light can also degrade the deck’s sealer or other finish. As a result, clean and reseal the deck annually.

Foot Traffic

Decks with a lot of foot traffic, such as commercial decks or those used frequently for entertaining, should be cleaned more often, every four to six months.

Foliage

If your deck is under trees or surrounded by plants, it might require more frequent cleaning due to falling leaves, pollen, and sap.

Are There Any Safety Precautions You Should Take During the Cleaning Process?

Cleaning your deck isn’t dangerous, especially if you avoid power equipment and hazardous cleaning chemicals. Even so, it’s wise to take a few precautions. Wear eye protection and gloves when using detergents. Long pants and a long-sleeved shirt are also good ideas. For the best grip, wear rubber boots or shoes. Old sneakers can also work, but avoid loose-fitting sandals like flip-flops. Be careful when working at the edges of elevated decks.