As winter fades and warmer days approach, it’s time to turn your attention to your outdoor living spaces. A deck that has weathered the cold months may look dingy and uninviting, but you can restore it with a little effort.
This guide walks through how to give your deck a thorough spring cleaning. In the video above, This Old House expert Tom Silva demonstrates effective techniques for cleaning and protecting your deck.
Assessing Your Deck’s Condition
Evaluate your deck’s overall condition before diving into the process. This ensures that your deck is safe for use and your cleaning efforts will be worthwhile.
Structural Integrity Check
Take a close look at the following elements of your deck:
- Fasteners and connectors
- Railings (check stability)
- Steps (assess sturdiness)
- Wood (look for cracks, rot, or mold growth)
If your deck is over 40 years old, be particularly vigilant about signs of carpenter ant or termite damage. Modern decks built since the 1980s often use lumber treated with insect-repellent chemicals, but older structures may be more vulnerable to pest infestations.
Safety Considerations
Make sure your deck meets current safety standards:
- Check that the railing height meets local building codes.
- Inspect the ledger board connection to the house for signs of weakness or separation.
- Verify that balusters are spaced no more than 4 inches apart.
Preparing for the Cleaning Process
Once you’ve confirmed that your deck is structurally sound, you’re ready to clean it. Proper preparation will give you the best results and protect your deck from potential damage.
Gathering Supplies
Collect the following items before you begin:
- Biodegradable wood cleaner
- Bucket for mixing cleaning solution
- Garden hose with spray nozzle
- Protective eyewear and gloves
- Pump sprayer
- Soft scrub brush
Protecting Surrounding Areas
Take steps to safeguard the areas around your deck:
- Cover nearby plants and grass with plastic sheeting.
- Remove or cover outdoor furniture and decor.
- Sweep the deck surface to remove loose debris.
Cleaning Your Deck
Now it’s time to remove dirt, grime, and potential algae growth that may have accumulated over the winter months.
Applying the Cleaner
Silva uses a pump sprayer with a biodegradable wood cleaner that he likes to use for decks and fences. He prefers this method over power washers, which are too powerful and can damage wood fibers. Here’s how to apply the cleaner:
- Mix the cleaner with water according to the manufacturer’s instructions. In the video, Silva uses a 1-to-1 solution of cleaner and water.
- Test the cleaner’s strength in a small area. It should be able to kill mildew and remove dirt in 10–15 minutes. If it takes longer than 15 minutes, the mix is too weak; if it takes less than 10 minutes, it’s too strong.
- Fill the pump sprayer with the solution.
- Apply the cleaner evenly across the deck surface.
- Allow the cleaner to sit for about 10 minutes to penetrate the wood.
Scrubbing the Deck
You’ll need to do some manual scrubbing after your cleaner has had time to work. Here’s how:
- Use a soft scrub brush to gently agitate the surface.
- Work in the direction of the wood grain to avoid damaging the fibers.
- Pay extra attention to high-traffic areas and spots with visible stains.
Rinsing the Deck
Once you’ve scrubbed the entire deck, here’s how to rinse it:
- Use a garden hose with a spray nozzle to thoroughly rinse the deck.
- Start from the highest point and work your way down.
- Thoroughly remove all of the cleaning solution to prevent residue buildup.
Treating Your Deck
Silva recommends using a borate treatment to prevent algae growth and wood rot. Follow these steps to apply the borate treatment:
- Mix the borate solution in a ratio of five parts water to one part borate.
- Use a pump sprayer to apply the solution evenly across the deck.
- Allow the treatment to soak into the wood without rinsing.
Allowing the borate to dry is crucial. This helps the treatment seep deep into the wood fibers, offering long-lasting protection. Silva recommends waiting two or three days before staining.
Sanding Your Deck
Sanding can help smooth out rough spots and prepare the surface for staining. This step is optional but can significantly improve the appearance and feel of your deck.
Sanding Process
Follow these guidelines for effective sanding:
- Make sure all screws and nails are below the wood surface. Sweep the deck if needed.
- Use a four-head random-orbit sander with 80-grit paper for the main deck area.
- Switch to a handheld random-orbit sander for edges and hard-to-reach spots.
- Sand lightly, stopping once the gray color is removed from the wood.
- Vacuum thoroughly to remove all sanding dust.
Sanding pressure-treated wood requires taking special precautions—check the EPA guidelines before you start. Remember that sanding isn’t just about refreshing the larger surface areas. Paying attention to your deck’s railings, stairs, and other intricate parts can enhance its overall look and feel.
Staining and Sealing Your Deck
The final step in your deck’s spring makeover is staining and sealing. This helps your deck look great and provides protection against the elements.
Choosing the Right Stain
Consider the following factors when selecting a stain:
- Color that complements your home’s exterior
- Level of transparency (solid, semitransparent, or clear)
- UV resistance for prolonged protection
Silva recommends using an oil-based stain mixed with a small amount of varnish for added durability.
Applying the Stain
A well-applied semi-transparent stain should protect your deck for two to three years, depending on sun exposure and weather conditions. Follow these steps to apply the stain:
- Pour the stain into a bucket and mix thoroughly before application.
- Use a paintbrush to apply stain around the edges of the deck.
- For larger areas, use a lamb’s wool applicator or roller.
- Apply the stain in long, even strokes, following the wood grain.
- Allow the first coat to dry for at least 24 hours before applying a second coat if needed.
Sealing for Longevity
Sealant adds an extra layer of protection to your deck. Look for one that offers both UV protection and water resistance. Silva recommends using a sponge applicator to cover the deck evenly.
Regular Maintenance Tips
Maintaining your deck helps extend its life and keep it looking pristine. Regular upkeep involves cleaning, periodic checks, and preventive measures.
Seasonal Inspections
Inspect your deck at the start and end of each season. Look for any signs of wear, damage, or potential issues:
- Algae growth
- Cracks or splits in the wood
- Loose screws or nails
- Signs of moisture buildup or rot
Cleaning Schedule
Regular cleaning keeps your deck in top-notch condition:
- Sweep the deck regularly to remove debris.
- Wash the deck every few months with water and a gentle cleaner.
- Reapply treatments and stains as needed, typically every two to three years.
Protective Measures
Take additional steps to protect your deck from environmental damage:
- Avoid using metal shovels or tools that can gouge the wood.
- Place furniture pads under legs to prevent scratches.
- Use outdoor rugs and mats in high-traffic areas.