How to Pressure Wash a Fence and Deck

This post shares all about how to pressure wash a fence and deck. Pressure washing is a simple way to make outdoor wood surfaces look new again. Learn how I used a Ryobi electric pressure washer to clean my wooden fence and deck posts with no extra cleaners or tools. Affiliate links below; read more about those here.

How to pressure wash a fence and deck

Today I am talking all about how to make an old fence look new again. How to give old, dull, or worn fences and decks a facelift by pressure washing them. (I’m also going to talk about staining, but that will be in a second post.) Our fence is only 2 years old, but it’s already looking worse for the wear after 2 full years of exposure to the elements. We’ve had our deck up for about 4 years in our backyard and have never finished the deck posts, so it’s about time. 

Make an old fence look new!

This post focuses first on how to pressure wash a fence, including tips on cleaners, the machine we used, the nozzle and PSI we chose, and more. I also pressure washed the posts that support our second-story deck because they are such a focal point in our tiny space. Let’s do it!

What is the difference between power and pressure washing?

They are basically the same. I actually didn’t even realize there was a difference until I started doing some research to fact-check myself for this post. The main difference is that power washers use hot water; pressure washers can use any temperature water. 

Both will work fine on most fences. Because a power washer uses hot water, it will probably be a better choice for fences that need more of a facelift. That’s because the hot water can help loosen the real grimey sections. Pressure washing is fine if you’re just got a fence with some wear—I’m using a pressure washer. 

Should I add bleach to my pressure washer?

Some tutorials online recommend adding a bit of bleach to your pressure or power washer to help get rid of mold. I’m not too keen on that idea because I found that some companies will void warranties and specifically don’t recommend bleach. That’s because bleach can negatively affect your pressure washer’s seals. It can also discolor the fence.

I also didn’t want to bleach residue in my yard, in my raised garden beds, and all around the air in such close quarters with neighbors—YUCK. If you have tough mold and mildew spots that you need to address, you can use a bleach solution and scrub those by hand with a stiff scrub brush. Then rinse with a hose.

Okay, how about another cleaning solution?

If your pressure washer doesn’t have a designated tank for detergent, you can scrub grimey areas with detergent and a scrub brush. Then use your pressure washer and just water to spray the spot clean. 

If your pressure washer has a detergent tank, make sure you’re using only detergents designed for your specific pressure washer. Check the manual, and if you don’t have it anymore, Google your brand and model pressure washer to find it. 

You can also use a special attachment to spray soap onto your fence. These attachments go on the end of your pressure washer’s spray gun and add your soap to the water as it’s being sprayed. I don’t have one of these, but it might be something worth looking into.

If you have a garden or plants by your fence, keep that in mind when choosing a cleaner. Make sure it doesn’t have ingredients that can hurt or kill your plants. To help discourage the soil around your plants from absorbing too much cleaner, you can pre-soak the areas with water from a garden hose. 

Whatever type of cleaner or detergent you use, make sure you work in sections, spraying bottom to top to avoid too much running and streaking. And don’t let it sit on your wood fence for too long. 5–10 minutes is typically enough. Then rinse thoroughly to prevent cleaning residue from interfering with your stain.

But I didn’t use any cleaner!

But guess what? I didn’t use any cleaning solution! Not even on the beams under our second-story deck, which had some NASTY mold stains. I just used the pressure washer, and look what an amazing job it did! The first three pictures below are the before pics; the last picture is the after pic.

I did go in to do some minor touchups after this photo was taken. I wanted to let it dry to make sure I got a good enough clean. The shadows kind of threw me off when everything was wet and I was trying to figure out where I needed to go over things a second time.

Should I stain a fence without cleaning it first?

No. Not unless it’s nearly new! But since you’re wondering how to make an old fence look new, your fence probably isn’t new. 🙂 Even if you just got your fence installed last year, it’s probably been through a lot already. Our fence is 2 years old. It has never been cleaned and we never stained or sealed it. It already looks pretty rough, especially compared to the brand new fences popping up around the neighborhood!

Ours has been through two whole years of exposure to the elements: rain, harsh sun, snow storms, ice, you name it. That leads to a lot of visible wear on a wood fence. It has some moldy/mildewy spots that we need to address as well. 

You shouldn’t stain your fence without cleaning it first because you want a nice blank canvas for your stain. A thorough cleaning helps eliminate things that could lead to an uneven stain. Take a look at this before and after—imagine trying to stain the before picture! That’s before pressure washing.

What nozzle and PSI should I use?

There are different kinds of nozzles and tips you can use with your pressure washer, and they have different purposes. A wider tip has lower pressure. Nozzles come in degrees. Do not use anything smaller than 25 degrees on a wood fence unless you really know what you’re doing—it can be too harsh and actually cut into the fence. 

A nozzle with a larger tip will be even more forgiving but still effective. Although working with the 15-degree tip my pressure washer came with could have probably been a bit faster, I decided to use the 25-degree tip my dad recommended. I’d rather go over the fence twice (if needed) than risk damaging or eroding the wood in one harsh pass since I’m not a professional.

As for PSI, 1200–1500 PSI is generally recommended for hard woods. Softer woods can be cleaned effectively with lower PSIs—higher PSIs might damage the fence. From what I read (and it was a lot), higher than 1500 for a wood fence could be risky. I really wanted to avoid that “chewed up” wood look that can happen when wood is pressure washed as too strong of a PSI/too narrow of a nozzle tip.

However, I’d read online that the Ryobi 2000 PSI electric-powered pressure washer is a great option for a fence, and my parents actually own one. So I decided to go with that and stand very far away from the fence to start so I could get a feel for how close I needed to stand.

I started about 6 feet away and got a bit closer once I felt comfortable. Then I tried to maintain about the same distance while washing to ensure the pressure remained the same.

Should I use a Ryobi Electric Pressure Washer to pressure wash a fence?

So as I said before, I borrowed the Ryobi 2,000 PSI 1.2 GPM electric pressure washer from my parents. They have used it on their vinyl siding, as well as concrete and wood. My dad recommended it as a great option for us to use on our deck area and fence instead of a gas-powered one, which he also has.

Here are a few details about the Ryobi electric pressure washer:

• 13 Amp electric motor, 2000 psi of force 
• Good for driveways, decks, windows, and other areas around the house—geared toward homeowners 
• Features a removable detergent tank for soap—do not use bleach with this pressure washer
• Has wheels and a handle for easy transport around the yard; equipped with an onboard hose reel for a 25-foot hose (which also comes with it) and accessory storage
• Comes with 3 nozzles: soap/water washing nozzle, 15-degree nozzle, and turbo nozzle

I used a 25-degree nozzle that my dad bought separately since I am not experienced working with pressure washers and was a little nervous about the 15-degree nozzle. It worked great on our fence. My dad had added a longer hose to his as well. Io I was working with about 50 feet of hose which was total overkill for our small space.

How to pressure wash a fence

As with a lot of projects, knowledge and prep is key. Once you’ve moved everything out of the way, decided whether or not you’ll use a soap or detergent, accepted the fact that you’re going to get soaking wet, decided on your nozzle and PSI, and hooked your pressure washer up…it’s time to go!

I washed the fence by getting into a routine of using long, smooth, fan-like motions to ensure the most even clean possible. Remember—more is not necessarily better with pressure washing! You want to wash until the color of your wood stops changing. Take off as little as possible to ensure the integrity of the wood fence remains intact and you don’t end up with any over-washed spots.

After pressure washing your fence, give it two full days of dry weather before staining. I actually pressure washed my fence and deck a month before staining it just because we have a toddler and have to work on projects like this when we can fit them in! I would just made sure to have two dry days before staining to ensure the fence is fully dry.

Make sure to check back soon for the post I’m sharing on the stains we chose to use for our deck posts and fence. We chose different stains for each, and I’ll be chatting about my rationale behind that. As well as some reviews of the products 🙂

Pin my tips about how to pressure wash a fence!