Wood decks require maintenance just like any other part of your home. This tutorial will walk you through the steps necessary for wood deck cleaning before refinishing.
Not all deck refinishing projects require you to go through this cleaning process. Your deck may just need to be power washed, but if your deck has been painted or you've used an opaque stain, you may have to go through this step.
Equipment / Tools
- 1 Eye Protection (goggles)
- 1 Rubber gloves
- 1 Paint scraper
- 1 Sandpaper
- 1 Stiff bristled brush (plastic bristles)
- 1 Plastic drop cloths (to protect plants)
- 1 Push broom (hard bristles)
- 1 Deck cleaner
Watch Now: How to Pressure-Wash & Clean a Wood Deck
Inspect the Deck (Annually)
You should do an annual inspection on your deck. Walk along the deck and look for any loose boards or other structural components, as well as rotting wood. Telltale signs of rotting wood include discoloration, mold, and softness when pressed with a hard object, such as a screwdriver. If any soft wood or dry rot is found, replace the piece.
Once you've looked everything over and the wood looks sound, you can prep the surface for staining.
Prepare Wood Deck Surfaces for Stain
The first step is to prepare the wood surface for stain by removing loose surface finishes and paint if needed. If your deck does not have loose paint or opaque stain, you can skip this step. If your deck is painted and you want to repaint it, you can also skip this step. This step is only needed if you have a painted or opaque stain and want to have a semi-transparent wood stain refinished surface.
Scrape Away Old Paint
Using a sharp paint scraper, remove any loose solid stain, paint, or finish.
Sand whatever does not come off by scraping.
Sealed film finishes such as varnish or paint must be stripped away with a chemical stripper. Make sure you have on your rubber gloves and eye protection when using a chemical stripper.
Apply Chemical Stripper
Apply the chemical stripper according to directions. Usually, you'll apply it in smaller sections and wait for it to work, then scrape the loosened finish away from the wood. For stubborn areas, you may have to apply the stripper a second time. You can also get in tight corners by using a putty knife. Rinse the stripper away as required by the instructions.
Types of Wood Deck Cleaners
There are a few types of deck cleaners or deck restorers on the market. They typically fall into three main types of cleaning base categories:
- Chlorine bleach cleaners: Avoid these types of cleaners. They will harm the wood and leave an unnatural whitewash appearance. They are also known to cause fuzzing of the wood fibers.
- Oxygen bleach cleaners: When mixed with water, these cleaners create hydrogen peroxide and a soda ash cleaning base. This is effective in removing mildew stains and graying caused by ultra-violet sun exposure on the wood. It's also effective in cleaning the wood of dirt and deposits. The wood returns to its original color after cleaning with this type of cleaner.
- Oxalic-acid-based cleaners: These cleaners do nothing for removing mildew stains but are effective for removing tannin stains. Tannins are naturally occurring, water-soluble resins of a reddish-brown color found in certain wood such as redwood, cedar, and oak. Usually, this type of cleaner is used as a supplement to oxygen bleach cleaners if tannin staining is a problem.
Apply Wood Deck Cleaner
Once the wood is scraped and stripped (if necessary) and you've selected and purchased a cleaner, you're ready to begin.
Prep Your Area
Prepare the surrounding area and protect your shrubs and plants with a plastic drop cloth. It's also a good idea to hose down the surrounding area with water to immediately dilute any deck cleaner overspray.
Put on your eye protection and rubber gloves before mixing the cleaner per the manufacturer's directions.
Spray the deck cleaner according to the manufacturer's instructions. Don't try to cover the entire deck surface at one time; work in sections for better results.
Don't try to cover the entire deck surface at one time; work in sections for better results.
Allow to Set
Let the cleaner sit for some time as recommended by the manufacturer, usually between 10 and 20 minutes.
Once it has been working for the specified time, scrub the deck clean with a hard-bristled push broom. Work with the wood grain, not against it.
Rinse and Repeat
Rinse with water and repeat the process on the next section of the deck.