This post was updated on August 16, 2024
Hello, I am Scott Paul, a leading exterior restoration contractor and business owner with over 30 years of experience in exterior deck and wood prepping. My wood deck prepping help tips are based on my history as a wood restoration contractor and actual hands-on testing. See here for more info about me.
I have updated our DeckStainhelp.com site with numerous new reviews and articles on deck cleaning products and how-to tips for 2024. We strive to remain your number one deck stain information source.
Please ask any questions below that you may have in our comment area.
Prepping and Cleaning a Deck
If you own a deck, you know the wood faces exposure to harsh outdoor elements all year long. That includes ultraviolet (UV) light from the sun, rain, ice, dirt, pollen, bird droppings, and much more. However, you might not have properly cleaned yours. Cleaning a deck with a top-quality wood deck cleaner will help loosen dirt, remove any grayish oxidation, and kill mold, mildew, and algae. It’s a must for regular maintenance and in preparation for applying fresh deck stain.
Are You Cleaning Your Deck at Least Once a Year?
Knowing how to clean a wooden deck properly is critical for homeowners. Whatever your climate, I tell people it should be done at least once each year. To get right to it, let’s review the proper deck cleaning process.
Preparing Your Deck for Cleaning
Before cleaning a deck, I always remove obstructions such as furniture, planters, and grills. Next, I’ll sweep the deck or use a leaf blower to thoroughly clear off dirt, leaves, and debris. To avoid accidental damage, I recommend covering gardens or other items with a tarp.
Next, you’ll select your product. Decide if you should use a deck cleaner or a deck stain stripper. Use a deck cleaner if the wood is gray and dirty. If you have an old deck stain that needs to be removed, you should use a deck stain stripper, as the deck cleaner is not aggressive enough to remove stains. Do you need more help on whether you should strip or clean the deck? See my Best Deck Prep. Clean, Strip, or Sand the Deck.
How to Clean Your Wood Deck
What You’ll Need to Bring
Gather the following supplies for the cleaning project:
- Goggles, gloves, and similar personal protective equipment
- 5-gallon (or similar size) mixing bucket
- A pump sprayer
- A stiff scrub brush
- A power washer rated at 3000 psi or lower
- A high-quality wood deck cleaning product. (see my best deck cleaner post)
A front porch partially cleaned and brightened.
5 Steps to a Clean Deck
- Pre-wet the deck surface with a garden hose or power washer on a low-pressure setting.
- Apply the deck cleaner using the pump sprayer. Make sure to mix the cleaning solution in the 5-gallon bucket first and then transfer it to your pump sprayer. In some cases, a powdered cleaner may not dissolve 100%. Take care not to pour undissolved powder into the sprayer, as it may clog it.
- After waiting 10 to 15 minutes for the cleaner to work, thoroughly scrub (agitate) the surface with the brush.
- Pressure wash the deck with the pressure washer in the 1500 to 2400 psi range. Rinse the deck well when done to remove any loose dirt nd wood fibers.
- Apply a wood deck brightener (often called deck neutralizer), which lowers the pH level to neutral and improves the appearance.
Composite Decks: Use a Different Brush
Composite deck board is usually composed of a blend of either polypropylene or polyethylene plastic and wood fibers. Although I’ve found that composite decking is durable and long lasting, the material is often susceptible to scratches from firm or abrasive brushes; therefore, I will use a brush with soft bristles. Remember to choose a deck cleaner that is appropriate for your composite material.
Can I Clean My Deck Without a Pressure Washer?
Yes! Although a pressure washer helps to speed up the process, a garden hose with a good nozzle can also rinse your deck reasonably well. Doing it this way will require more scrubbing while using your wood cleaner.
My Deck Cleaning Tips for Success!
- Ensure the deck is clear of all furniture and grills before starting.
- First, decide if you should use a deck cleaner or a deck stain stripper. Use a deck cleaner if the wood is gray and dirty. If you have an old deck stain that needs to be removed, you should use a deck stain stripper, as the deck cleaner is not aggressive enough to remove stains. Do you need more help on whether you should strip or clean the deck? See my Best Deck Prep. Clean, Strip, or Sand the Deck.
- Pre-wet the deck before applying the deck cleaner. Take precautions to wet all vegetation and the surrounding house. Most deck cleaners will not harm plants as long as you pre-wet and rinse off any residual cleaner that comes in contact with them.
- Wait about 5-15 minutes for the cleaner to activate. On hot days, mist the deck with water to prevent the cleaner from drying.
- Using a stiff scrub brush, agitate the deck until the wood comes clean. A pressure washer at 2400 psi or less will speed up this process.
- If any stubborn areas persist, then repeat the process.
- After thoroughly cleaning the deck, rinse the house, deck, plants, etc., to remove all the loosened grime.
- Using a Wood Deck Brightener will boost the wood’s appearance. The brightener neutralizes the deck cleaner and “brightens” the wood to a more natural state.
- Let the wood dry for at least 24-48 hours before applying a deck stain or sealer.
My Top 4 Deck Cleaner Reviews
See this link for my in-depth article and deck cleaner reviews.
My #1 Best Deck Cleaner | My #2 Best Deck Cleaner | My #3 Best Deck Cleaner | My Honorable Mention |
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From: $64.99 *Ships Free | From: $64.99 *Ships Free | From: $35.99 *Brightener Additional | From: $49.99 *Ships Free |
Best Deck Cleaner 2024 Video
Watch my deck cleaning video!
Do you have to clean and scrub the railings, posts and non-floor surfaces of the deck too or just the floor surfaces? Or will a power washer be ok for all other non-floor surfaces before staining. Thanks so much!
Use a deck cleaner and pressure clean all wood that will be stained.
What is the best process order if you are sanding prior to staining? My plan is to clean, sand, brighten, stain.thanks!
Your order is correct.
Can I rinse off the deck with water after sanding the deck to remove the dust and other particles resulting from sanding and then wait 24 hours to stain the deck?
Thank you
Yes, but wait 48 hours.
Can the deck be cleaned and then brightened in the same day? Is it okay if it rains after it is cleaned and brightened but before the stain is applied?
Yes and yes. Just let dry after it rains for 24-48 hours.
We have a 5 year old deck with PT wood. We had previously used a tinted Thompsons Water Seal on it. Plan to sand the entire deck floor to remove all old stain (most of it has worn off & the wood looks gray). After sanding & washing it off do we then have to also use a cleaner or can we just use a brightener?
Clean and brighten would be best.
I did the RAD cleaning and brightening but now the weather has been extremely unhelpful so I am going to go over the two week window that you suggest. What do I do? Do I have to start from the beginning and clean and brighten the whole deck again? Or can I just brighten it? …
Lightly pressure rinse and apply the brightener. No need for a cleaner yet.
Great! Thank you. Follow up question; since I’ve been getting so much rain I want to be sure. I am using the Armstrong Clark Semi Transparent, how long after I stain it is it safe if it rains? I thought I remember reading you said it could rain on it pretty quickly … ?
AC says it can rain on it within 4-8 hours, but we prefer the next day to be safe.
I am preparing to refinish a 4-year-old cedar deck that has been previously stained with a semitransparent stain but was power washed last summer but then sat through an Alaska winter unstained or otherwise protected. There is a new gazebo structure on the deck, stained last August (I intended to stain the deck too but rainy weather and then onset of winter intervened). So I have a couple of questions:
1. My stain says only apply when temp is above 50 degrees and will not dip below 50 for at least 48 hours. We are still getting night temps in the mid-40’s here. Does this just slow the drying process or will it actually affect the quality of the stain if I apply and it gets below 50 that night? (Only one coat of stain is needed, so slow drying is acceptable to me.) The product I will be using is Cabot Australian Timber Oil.
2. Second, there is a bit of scattered mildew on the surface. Can I carefully apply a cleaning solution with bleach in it to address? I don’t want to use a commercial cleaner on the whole deck because I can’t protect all the newly stained gazebo boards from that treatment. I was just planning to sand with a random orbital sander with 80-grit to prepare for the application of the stain, because I can keep away from the gazebo boards by doing it manually. What do you think?
Thanks for your website, it has some great info on it. I can tell I’m being a bit outside the usual process by just wanting to sand, but am not sure how to protect the gazebo otherwise! Thanks for any insight you can provide.
1. It will slow the drying and curing but should not harm the coating.
2. Bleach is bad for wood and you cannot spot clean. All the flooring should be cleaned and brightened for the prep. Sanding is not a good way to prep. Closes the grain of the wood, reducing absorption.
The cleaners should not harm the stain on the gazebo much or at all.
What is the best prep method before staining? I see two opinions on the web. Clean, rinse, sand and rinse again (to raise grain slightly of weathered pt deck and rid sawdust) OR clean, rinse, sand then stain? Maybe sweep dust away but no final wetting due to rinsing or RAIN. Even cover with tarps to keep dry. Thank you
Clean and brighten. Sanding is typically not needed.
If I have cleaned and sanded pt wood with 60-80 grit with vacuum attached; is it best to rinse the wood and let dry 3-4 days, then stain . Or keep dry after sanding and stain right away. I have read that if it rains after sanding you must clean and sand again! WTF! So … sand, rinse and stain Or … sand and stain? Thank you.
You do not have to clean and sand again after a rain. Nothing would ever get done if that was true. If we sand, which is rarely as it closes the wood grain, we would do in order.
1. Clean deck and let dry.
2. Sand lightly but no more than 60-80.
3. Apply the wood brightener and rinse well to open the grain some and remove sand dust.
4. Let dry for 48 hours and stain. If it rains, just wait until it dries for 48 hours.
Will pt wood sanded (60-80 grit) have greater porosity and thus absorb stain better if kept dry (possibly tarping) or would rain open more wood pores and therefore permit stain to absorb better? (48-72 hours drying time.) Thanks.
Raining on it will not matter. Just leave uncovered.
Will the Defy deck stain stripper harm the screen that is on my deck?
Depends on the type of screen it is?
I have a deck on my second floor roof, When I use a cleaner to clean the wood won’t the cleaner leak down to the sides of the house and stain the siding. Or is there some other way to clean without causing the leaking
Pre wet an rinse the siding when done. It should be fine.
Questions on board condition and stain type to use?
I apologize if this turns out to be a duplicate entry…
The boards on our deck are weathered and have mildew but they are firm and not spongy. Seems to be PT wood and it looks like the previous owner had applied a semi-transparent stain but I can’t say for sure given my lack of experience. Deck is in the DC metro area and shaded by trees if that helps….gets mostly indirect sunlight with a a few hours of direct light.
1. I am wondering if cleaning these boards will be enough or should I plan on sanding and/or replacing as well? Pictures attached.
2. Same question on the railing top – do I need to replace it?
Regarding stains, I am considering going with a semi-solid stain on deck flooring if I end up replacing some boards once we start the project. This is mostly to make the old and new boards blend better. However, I also saw guidance from one stain manufacturer recommending their solid line over semi-transparent for older boards.
3. Do semi-solid stains work significantly better for protecting older/split wood boards than semi-transparent stains or would with either stain type work?
4. Do semi-solid stains also have peeling issues like the solid stains?
5. Do they require sanding to remove (like solids do) prior to re-coating in a couple of years with another semi-solid or transparent stain?
Thank you for this great site!
1. Strip and brighten all for the prep.
2. same as 1
3. Not significantly better, but you cam get a little longer UV protection.
4. Depends on the brand. Some film on the wood and are prone to peeling. Some soak in.
5. same as 4
Thank you!
How long do you wait to use brighter after cleaning deck
Right away while wood is clean and wet from the cleaner.
Will Restore-a-Deck Brightener work well after using the Defy Stain Stripper, in preparation for applying Defy Extreme stain?
Yes, that will work.
Two of my planks have some rot in them, and when I powerwashed the deck it left some large indentations. Is there anything I can use to fill the indentations before I stain the deck? Thank you for your help!
Wood filler does not work well with exterior wood and the filler will not blend with most stains. Best to replace those boards if possible.
My deck dried before I got the brightened on it. Is this a problem?
Just apply the brightener when you can.
I used Penofin wood cleaner on my
new Cedar deck. I have also power washed it. There is still a thin tissue paper like white coating over much of the wood. Don’t know what else to try. Any ideas? I am attaching a photos.
That is oxidized wood fibers that have not completely come off with your prep. Wash again to remove or lightly buff them off with a floor buffer and sanding pad.
https://www.deckstainhelp.com/wood-fuzzies-furring-on-deck/
My main flooring is gray and needs sanding, staining and brighten. But the vertical railings and support beams still have some color. Do I strip those areas first? Or will pressure washer + clean/Brighten work? Staining the same color. Replacing one handrail beam too.
If you are using the same color and brand, just use a deck cleaner and pressure washing for the prep. Brighten after. You should not have to strip the railings.
We just installed a brand new deck with azek composite decking. The handrails, joists and support posts are all pressure treated cedar. Do I have to sand the cedar before applying stain? Do I need to use wood cleaner, wood brightener for brand new deck before applying stain. What order should these steps happen?
Thanks
See this about new wood:
https://www.deckstainhelp.com/staining-a-new-deck/
Regarding my previously stained, weathered cedar deck, should I sand first and then use a cleaner, or clean first then sand? I am not planning on stripping.
You would clean, let dry, lightly sand, then brighten.
Finished a cedar deck in WI three years ago. I let it dry for a year and used RAD and Armstrong Clark semi-transparent stain with great results two years ago. Am going to re-stain with same AC stain this year. How should I prep? Full RAD or just cleaner or brightener?
Use the RAD Cleaner and Brightener kit for the prep. Post some pictures when done if you can!
Is there any harm in applying stain a week or two after cleaning? There are only so many free hours outside of our day-jobs…wanting to stain boards & didn't know how long it is acceptable to let boards sit untreated. My thought is it doesn't matter too much as long as free of debree. Ideally, wouldn't let any dirt accumulate, but it is impossible for me to complete the desired two coat application on consecutive days.
We always try to stain 48 hours after prep if possible but up to 2 weeks if the weather does not cooperate. Longer than two weeks and you may need to reclean.
About to stain (w/ATM) a pressure treated pine deck 3 years old. Some black mold due to wet winter last year, I attempted to remove by spraying with vinegar and follow up with baking soda/water mix. Hired a guy to stain who has sprayed it with a cleaning Clorox and pressure washed it. It doesn't look very clean and there are still gray spots from the mold on some rails.
Overall it looks cleaner than before but before he stains it is there anything else I need to do to prep it for optimum outcome?
The main prob for my east facing deck is rainstorms, weather not so very bad here in AL.
Try using products that a designed for this prep. Use the Restore A dEck Cleaning Kit and pressure washing to prep.
We just sanded our Cedar deck today. We have a cleaner and brightener to use before staining. The sanding took care of all the black/mold so was wondering if I need to still clean it or just brighten now?
It's supposed to rain in two days, should we clean and brighten before or after the rain? Will the water be a problem for the newly sanded cedar? I always thought once you go down to bare wood it's not supposed to get wet.
Thanks so much!
Do not skip the cleaning. Go ahead and prep now. Rain has no effect after prep. Just make sure it dries for a couple of days after the rain stops.
I powerwashed my 15 year old deck about 4 weeks ago and then had lots of rain. It hasnt rained in the past week, but I spilled a good little splash of water on the deck while giving it another final clean. Should I go ahead and add brightener this weekend then look for the next dry weekend to stain?
Yes that would help.
I have a cedar deck I stained with Wolman F&P two years ago. The stain is holding up well, but starting to wear due to weather and foot traffic. I would like to clean the worn areas with Wolman Wood Clear and Brightener and reapply the same F&P product to coat and protect the cedar.
Do I need to use a stripper and go all the way down to bare wood or is the cleaner/brightener sufficient when prepping wood and reapplying the same product previously used?
You should be good with cleaner/brightener as long as it preps evenly. Meaning you do not want some areas bare and some areas with stain still on. This could result in an uneven appearance.
does washing new cedar with dawn dish soap before you stain it, clean it effectively?
No, you need a deck cleaner and a wood brightener to remove the mill glaze and any oxidation.
I just power washed my redwood deck and cleaned it with Olympic Premium Deck Cleaner. Now it looks WHITE with no color of Redwood at all. Did the cleaner ruin my color on my deck? Is there something I can do to fix it? Nervous, nervous, nervous.
Brighten the deck and then stain it. It should come back.
I forgot to say I brightened it as well. It dried completely white. I will go ahead and stain it and hope all the beauty comes back. Thanks for your reply….you help a ton of people.
I have a 4-year-old deck. It doesn't get a lot if use so it's not overly dirty just light wear. I wash it annually with a foaming cleaner and restain with Armstrong Clark Stain. Should i be using such a deep cleaner every year or is there something less harsh that wont strip off the stain.
What you are using sounds fine.
Do I need to use a deck cleaner, or is a pressure washer just as suitable?
Use a deck cleaner and a wood brightener.
I sanded my deck to remove a sloppy paint job done by the previous homeowners, then cleaned it with Olympic deck cleaner. The forecast is calling for rain for the next several days and I don't know when I'll get to stain. How long can I wait to stain without damaging the wood?
A couple of weeks should be okay.
Our deck is old, we power washed it, but it had mold on it I think, it was slick when wet. I was told to clean it again with TSP and then rinse that off, then wait to dry again before I stain or waterproof. is the TSP washing necessary?
You should use a deck cleaner that is designed for this and pressure wash. TSP does not clean thoroughly. We like the Restore A Deck kits.
We put a new cedar deck on 12 months ago. We now want to stain it. The deck had grayed over the winter. I have cleaned the deck with Thompson's 3in1 (no bleach) wood cleaner and rinsed it well – amazing the gunk that rinses off! The cedar deck now has cedar color areas (as expected) but also white color areas (not expected). Why the white areas? Shall I clean it again with the Bher cleaner prior to applying the Bher semi-transparent deck stain?
Clean with a better product and brighten. Use Restore A Deck Kits.
If I clean and brighten my deck and it rains do I need to do it over again?
No. Just let it dry before staining.
I have a new cedar deck. I read allot of comments below. I'm curious if the spindles and rail need to be cleaned and brightened as well a the floor. Also, how long should you let new cedar weather. My deck is in full sun.
Yes all new wood needs to be prepped. As for weathering, we normally wait 2-4 months, but this varies based on the stain brand you choose. Just one coat of stain for new cedar.
I just finished using RAD stipper on my deck and would like to use the brightener but it's going to rain tomorrow and then dry for several days. Should brighten it now or after the rain? I'd prefer to do it now since it will rain later next week and I want to try to fit drying and staining between the rainy days. Thanks so much for your advice.
Brighten now.
I used messmers deck stain and some of it sprayed onto my trees. We rinsed them off but I'm worried that they will die. Is there anything I can do or should they be ok?
There is nothing you can do at this point and hopefully they will be okay.
I am painting my deck with a deck-over type paint. I power washed it to clean it and get the debris and mildew off the wood. It was painted previously, not stained. Some spots had to be sprayed down to the bare wood. Do I need to use a deck cleaner since I power washed it already, or is a power wash good enough?
Depends on the brand of paint you are using. Best to follow their directions.
I cleaned & brightened my deck yesterday morning. It looks pretty good, but I noticed some fuzzies, particularly on the cedar part of the deck. I've read a simple palm sander should do the trick, but I'm curious if I would have to re-brighten after, or just a good rinse and read to stain?
Just rinse well and you should be fine.
I have a 2000 square foot deck that i have been rebuilding in phases. I am now nearly done, and some of the pressure treated pine boards i have installed are now over a year old and have grayed, and developed small black dots on them. I understand that i must clean and brighten the deck before i can stain everything. I plan on using the restore-a-deck system. You guys recommend using a stiff bristled brush, along with a pressure washer at 1000 psi to aid in the cleaning. My pressure washer is 3100 psi with no pressure adjustment. Will it suffice if i use a wide fan nozzle and keep my distance? I know pressure washers can easily damage a deck, but would my pressure washer be effective if i kept my distance?
Yes you can use your pressure washer. Washing at say 8-12 inches away and the psi will drop in half. Use a sweeping/pendulum motion while washing.
My deck has aluminum spindles around the whole deck. Is it necessary to protect these prior to cleaning? Will be using a pump sprayer to apply cleaner and power washer to clean deck.
Matt, it has a lot to do with the spindles, not the cleaner. Some have a protective coating on them that the cleaners will not harm while others do not and the cleaners can create spots. There are some many different manufacturers of the spindles that it is impossible to say for sure without actually testing.
Sorry, I just posted this same question in a different forum, didn't notice this response. Not clue if they have a protective coating. They are plain black and after one hot summer and a Canadian winter they look in great shape. Is there any way to "test" them to find out? What will the spots look like and how long would they take to set in?
Usually if they have a smooth finish then they have the protective coating. Rough or a powder finish, they are not protected. The cleaner or brightener would react be creating \”spots\” that could be lighter or even darker on the spindles.
I have a brand new deck that I'm going to stain this weekend. I'm planning on cleaning it tomorrow since it will be a sunny day, then staining it this Saturday. We're supposed to get rain the next 2 days, then have plenty of sun Friday, Saturday & Sunday. Is it ok that the newly-cleaned deck is going to get some rain before I stain it? I'll make sure it's totally dry before I stain Saturday. But I wasn't sure if the rain would effect a newly-cleaned deck. Thank you!
No, rain will not affect a new deck. You do realize new wood should be weathered and prepped first:
https://www.deckstainhelp.com/staining-a-new-deck/
I installed a new floor and handrails to my deck August of 2104. The posts, railings and steps are painted with a Cabot solid color chestnut brown acrylic deck stain – they were not replaced. Is power washing and/or deck cleaner recommended on the entire deck? And deck brightener too? Also I want to paint the railings, handrails, posts and steps white. But I want to stain the new wood floor a dark color stain that shows the wood somewhat. A company I am getting a price quote from uses Amstrong Clark products. Is this a good choice? I live near the shore in NJ and my deck gets a lot of sun. One more question…one application or two this year? Thank you.
I forgot to ask if sanding is needed? And the company wants to power wash…is this ok?
Pine decking from Lowes
No sanding. Prep with deck cleaner, pressure washing, and brightener.
Yes the Armstrong would work well for the floors. One coat on new wood.
Company says they will use either Armstrong Clark or Ready Seal for floor. Which do you recommend? And Pittsburgh Paint for rest. Is this an ok product? And next yr will I apply 1 or 2 coats on floor?
Armstrong Clark for floor. Pittsburgh will be fine for a solid stain. 1 coat next year to floor.