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How to Clean a Deck

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DEAR TIM: I am having a spirited debate with my husband about how to clean a deck. Deck cleaning doesn't seem that hard, but my husband wants to use a pressure washer thinking it will save time. I want to use a green cleaner that is non-toxic and environmentally safe. What is the proper way to clean a deck and keep it looking nice? Lisa T., Burlington, NC

DEAR LISA: Cleaning a backyard deck is not supposed to create marital strife. In this instance, I think you and your husband might be able to reach a compromise that allows each of you to clean the deck in the manner you see fit. I have cleaned countless decks, and there are pros and cons to each of the methods you mention.

Let's talk about pressure washers. These tools are extremely popular that appeal to homeowners. Pressure washers are like shoes - they come in all different sizes and the end of the spray wand can be equipped with different tips that concentrate the high-pressure stream of water. The stream of water that is thrust from the tip of the wand mechanically agitates the surface of whatever it strikes. This is what cleans.

You have at least two choices when you decide to clean a wood deck. Here are two of them - a pressure washer and oxygen bleach.  IMAGE CREDIT: Tim Carter

You have at least two choices when you decide to clean a wood deck. Here are two of them - a pressure washer and oxygen bleach. IMAGE CREDIT: Tim Carter

 A pressure washer can clean a wood deck much faster than you can do it scrubbing by hand. That is a terrific advantage. But one of the side effects of a pressure washer is that it frequently destroys the surface of the wood. The stream of water can be so powerful that the light-colored spring wood fibers are eroded by the water. Those that are not eroded can be dislodged so that the wood is fuzzy or rough after it dries.

Professional deck cleaners argue with me that this only happens when an inexperienced user is working with the tool, the pressure was too great, the tip used at the end of the wand produced a stream of water that is too harsh and/or the tip is held too closely to the wood surface.

If you decide to use a pressure washer, then you better test it or have the professional prove to you they can use the tool and not damage the wood. If you are really interested in making your deck-cleaning project a green-cleaning activity, you should give serious consideration to the secondary effects gasoline or electric-powered machines have on our environment.

I am a big proponent of non-toxic cleaners. The older I get, I have this sneaking suspicion that certain chemicals we encounter in everyday products are responsible for many health issues. I am not a doctor, but common sense tells me that harsh chemicals are not processed well by our bodies.

Years ago, I discovered that there are different types of bleaches - one of them being oxygen bleach. Many people think bleach is bleach, but the bleach found in most homes is chlorine bleach. The active ingredient in chlorine bleach is sodium hypochlorite. Check the label of many bleaches or deck cleaners, and you might see this chemical name.

Oxygen bleach is a powerful cleaner that is just about as green as you can be. It is commonly available as a powder. The chemical makeup of the purest oxygen bleach is simply hydrogen peroxide and soda ash. When you mix this type of oxygen bleach with water to make a deck-cleaning solution, all you create is more water, oxygen and soda ash.

The oxygen bubbles in the solution do most of the work done by the pressure washer. The solution soaks into the dry wood and the oxygen ions deep clean the wood by breaking apart dirt, algae and mildew molecules. The solution is not toxic to you nor any of the plants, bushes or trees around your deck. You can't say that about chlorine bleach.

But the con about using a green cleaner is time and elbow grease. You will have to do some additional mechanical agitation using a scrub brush on a pole to get your deck squeaky clean. However, you will be pleased to discover the wood will not be fuzzy, and there will be hardly any erosion of the soft spring wood.

My advice to you is to use oxygen bleach to clean the deck and have your husband help you with the scrub brush. If he must use his pressure washer, have him insert the 35-degree tip and just use the machine to do the final rinse. But if I was your helper, I would simply use a garden hose with a regular nozzle.

There are many different oxygen-bleach products on the market. You can see them on TV informercials, in warehouse stores, in grocery stores and from online marketers. As you might expect, there is a big difference in quality. The less-expensive oxygen-bleach products often contain less of the active ingredient, and they use an active ingredient that might contain impurities or inorganic chemicals.

The purest oxygen bleach is made from raw materials that are food-grade organic chemicals. You can't get any greener or purer than that.

Years ago, when I first learned about oxygen bleach, I studied it in great detail as it fascinated me. I never liked the harsh characteristics of chlorine bleach. The more my wife and I studied and tested the oxygen bleach, the more we liked it. So much so that we use it to clean anything water-washable around our home. Furthermore, I felt so confident of its appeal, I started my own little company to sell the highest-quality oxygen bleach. Full disclosure and transparency is required in today's world, so you need to know that I am both a believer and a seller of this amazing product.

Message from Tim:

Years ago while researching a column about cleaning decks, I discovered the wonders of Oxygen Bleach. It is perhaps the 'greenest' cleaner I know of as it uses oxygen ions to break apart stains, dirt and odor molecules. There are no harsh chemicals, and it works on just about anything that is water washable.

I decided to create my own special blend using ingredients made in the USA. In fact, the raw materials in the active ingredient are food-grade quality registered with the FDA. I call my product Stain Solver. I urge you to use it to help with cleaning your wood deck. You will be amazed at the results!

Column 726


17 Responses to How to Clean a Deck

  1. Thank you for your professional advice. This is my first deck and I want to do this right. Can you please let me know where I can find your product. (Stain Solver). Thanks again

  2. Can you advise how best to clean between the boards on a deck? Some of the boards are cupping as sand, dirt, and leaves have blocked the gaps between boards and water is not draining away.
    I would like to use a pressure washer to blast the build up away but my wife thinks that will damage the timber allowing more water to soak in and causing more cupping. Please help!

  3. In many places I have read that you should use a "brightener" after using a cleaner to correct the PH before applying a sealer/stain. But you don't mention using a brighten in your ebook, "Cleaning and Sealing Your Deck". Is a brightener needed after using oxygen bleach?

    • In my opinion, it's all hype. It's been 43 years since I was in my college 5-hour physical chemistry class, but I can tell you this for a fact. The cleaners, like my Stain Solver are alkaline. Water is for the most part neutral. Brighteners are acidic. If you had acid in a beaker in the lab and you rinsed the glass beaker well and even rubbed it, the glass surface would be neutral as you washed away all the acid.

      The same is true for wood. Sure, if you leave on the cleaner and don't rinse it, it needs to be neutralized. But rinsing does that for you if you rinse and scrub well making sure all the alkaline cleaner is gone from the surface of the wood.

      Can a little remain in the pores of the wood? You bet! But what happens if you use a Brightener? After you rinse it off will some of it remain in the pores of the wood leaving the wood acidic?

  4. Does a sanded deck need to be cleaned with cleaners such as oxygen bleach? I just sanded my deck and have found lots of mention about properly prepping a deck for staining but none seem to mention what to do if you have sanded it right down. I used 36 then 60 grit using a commercial floor sander. I still see some tannin bleeds around some of the nail holes.


  5. I have an unfinished deck built last year that I need to wash then stain. this deck has a stainless steel cable system that I am afraid will be damaged by the caustic cleaners on the market. I spoke with Behr and they would not confirm that their all in one cleaner would not harm the cables but said that the wood must be prepped prior to painting. The cable manufacturer had no advice either. I purchased simple green hoping it would not hurt the railing system but it does not recommend you use it on unpainted wood, so I am at a loss as to what to do. Does anyone have any recommendations on what cleaner I should use that will not hurt the railing system but properly prep the wood?

    • Brian,

      My Stain Solver will NOT hurt stainless steel. We have lots and lots of Before and After photos of it being used to clean SS sinks and commercial coffee makers. Plus, I've used it myself for nearly 20 years to clean all the stainless steel around my house.

      Go to: Stain Solver It's an amazing wood cleaner too!

  6. Did I read this right? Once unfinished or sanded wood decks get stains...you can't remove them. Any suggestions?

  7. Interesting dialogue.
    My mom's Lumberock deck has been cleaned several times, but it never gets white enough. Are there commercial scrubbers out there to make the deck look brand new again?

  8. Are there any cons to using product prior to painting? I.e. - Will the paint seal properly? Will it affect the bond of the paint to the deck? Will the paint peel? I haven't been able to find enough on the subject.
    I'm using Behr Dekover.


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