Help me learn deck cleaning

I promised myself I would not clean decks until I took classes to clean them properly cause they scare me to death. But of course I don’t listen to myself. So I have two decks next week and am pretty lost here. So any and all help would be very welcomed.

I have a 4gpm 4000psi cold water pw if that matters.

Deck 1: the deck is in great shape and was stained last year. All the customer wants is a cleaning cause there is one big mildew spot about 1 by 2ft and other scattered small mildew spot.

I think i need a percarbonate cleaner like F-10 from pressure Tek. I assume that I would mix in some ratio and down stream onto the deck then maybe brush it. Let it sit around 10 mins, never letting it dry, and rinse off. Now should I just rinse off or use a 40 degree tip at around 800-1000psi three ft and rinse.

Deck 2: luckily it’s for family but my cousin wants it stripped sanded and stained. I know I have to use a stripper and a neutralizer to balance out the ph before I stain.

Like I said help…

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For deck one I would use house wash mix to clean it. You will need some sh to kill the mold and mildew. If its really has a buildup of dirt use a percarbonate cleaner than the house wash mix if needed. For rinsing we use a 2510 tip to rinse. We hold it about 6" above the wood or just high enough so the fan pattern is a little wider than 1 board. Here’s where it gets difficult you need to start at one end and move continually to the other end. Don’t stop don’t go back and forth. If you do you will leave marks on the deck. If you need to go back over a board do the whole board.

Deck two what does it have on it that needs to be stripped off? Once you know what’s on it than you can figure out what needs to be used to strip it. The most difficult to do are the latex based sealers. Pictures would help.

Ok well I feel much better about deck 1. It’s in pretty good shape. Just needed to hear or i guess read that. Thank you very much.

As for deck 2 I’ll get some picks and post them tomorrow.

I agree with everything Charles is saying but I can add one tip for ya. This may take a little more practice but it will speed things up for you in the long run. If you do like Charlie says you will be fine…but the more decks you do you won’t have to follow any boards down and then back unless your staining them with a pad or brush where you should follow the board to the end so you don’t get Lap marks from where the stain ended and then you started there again where it was partially dried and then you have what we call in the biz “Lap marks”

Learn how to fan out with your wand while Powerwashing a wood deck and you can move at a rapid pace. You start on one corner and work straight back from where you started from. With one swing of the wand you fan down towards the wood then go along and then fan up so you don’t scar the wood. Do this all the way down walking straight back. Then when you get to the back of the deck turn around and now walk backwards and do another section all the way to the front. Remember where the spray meets the part you cleaned already then fan up and away… You’ll do a deck twice as fast this way but it may take you a couple of decks to master the “swipe” with the fanning coming down and going back up…

If your nervous to do that for now then Charlie’s way of following a board board all the way to the end may be your best bet for this deck.

Good luck

Im doing my deck this weekend…

My front porch has been waiting for stain for two months now.

I have been cleaning decks, since I started pressure washing a couple years ago. Many people are so thrilled to have their deck cleaned and that doesn’t even cross their minds until you suggest it. The customer satisfaction is always worth the hard work. The first deck that I cleaned was completely black from the build up on it. It took repeated scrubbing and a lot of elbow grease, but the wood was actually preserved under the 1/8 inch thick black layer of junk. I have always used oxy clean or baking soda and hydrogen peroxide and a deck brush. I follow up with a 2510 tip and the end result is amazing. However, one deck had green stains on it that I couldn’t get off with that mix. I tried some SH and it still didn’t come off. Where I used the SH the deck was lighter than the rest of the wood, as if it stripped the wood color. I had to go back and bleach the entire deck with SH. What is that green stuff and what is the best way to remove it?

Also, I like to avoid using SH on wood at all cost because of the discoloring. How do others feel about this? What are the best practices when it comes to wood/deck cleaning?


Shhhhhh don’t tell anyone. In the 90’s the first couple of years in my business I never used any chemicals. I drilled everything but I did always go with the grain of the wood… The only complaint I ever had back then was deck staining and it was rare… But there was a couple of time and same goes with a house where I left lap marks because I didn’t follow the boards all the way down… BUT… Back then it seemed like most decks and wood houses I did the people never ever had them cleaned…

You guys have no idea how lucky you are to have the net and PWR at your fingertips to learn…

We also try to avoid using sh on decks. I prefer using an oxilic acid, or citric acid mixture as it will help bring the deck to its natural Ph. Giving it its natural look. The acid mixture will break down most organic material that is on the deck. If there are any other stains I would treat them individually.
On deck 2 with a strip we use sodium hydroxide, let it dwell keeping it wet so it will stay active until the stain starts to lift then rinse. There will be areas of darkening on the wood, ideally you will want to try to avoid this so you don’t have to sand as much. Once rinsed and stain is removed. Brighten/neutralize with your oxilic acid, rinse thoroughly. When doing a full strip we usually sink all screws/nails, and sand everything. Then apply the stain.
We sand most decks so that we can even out any tough stain left in the knots and other stubborn areas. Charge accordingly and give options. Some people don’t want to pay for a new looking deck, they only want a “band-aid” helping cover the areas where stain has failed.
I hope this helps.

Sent from my DROID RAZR using Tapatalk 2

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The deck cleaning course contains all of the information you need to proficiently restore wood exposed to the weather. The class is trained by some of the most respected and well-informed pressure washing contractors in the industry. Go and search for the course, you may also apply online for this kind of courses.

Basement cleanup New Jersey

Hey guy’s what is sh? Is that bleech?

I precleaned a deck this morning going to go back and give it a light sand and stain on Friday the owner did not want me to strip the old stain but I am aware of the type of stain used previously which I’ll just be applying a couple more coats of iv done this on another deck previously came out great. My only question is from what iv read about applying the stain you test the timber by applying a drop of water if the timber absorbs it, it’s ready to be sealed but it’s been raining all day and looks like it’s only starting to clear on Friday. Most likely the deck will still be wet should I give it a good week to fully dry out or can I apply the stain on Friday?

Wade Cull

Poseidon Pressure Cleaning Services


do you reccomend anything particular

for a cleaner

Dude…This thread is 7 years old. Some or all the folks are not active any longer…


Use the search bar. there are a lot of relatively current posts

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Fanning is all we did on all the Nantucket decks. We used Cedar Wash first, dwell at least 20min then start fanning. Unsuccessful fanning results in what we used to call zebra stripes. When you get tired the lance isn’t raised up as much as you think.