Should You Power Wash Trex Decking?

Trex is by far the most popular brand of composite decking we install. In fact, the name has become synonymous with all types of composite decking. When we’re called to build a new composite deck what the client generally asks for is a Trex deck. It’s a fantastic manufacturer with a good warranty and a wide range of great products. But what about long term care and reliability? How do you keep a new Trex decking looking like new? Can you power wash Trex? What types of cleaners are safe to use on it? And what about older Trex decking?

I do not recommend using a power washer on older Trex decking. The pressure could damage the decking and void the warranty. We’ll list the models later on in the article. The newer Trex models that can be power washed include Trex Transcend, Trex Enhance, and Trex Select. When you power wash composite decking, use a fan attachment and low pressure. The washer should be held at least 8 inches away from the deck at all times to prevent any damage. I like to keep my pressure in the 1500 PSI range. Trex says you can go to 3100 PSI but I never go that high. Low pressure with simple soap and water is generally enough to keep Trex clean. If you need more cleaning power, try a commercial deck cleaner approved for use on Trex. We’ll link to some later in the article.

Pressure washers are powerful tools that can damage a deck’s surface if they’re not used properly. Never use anything but the fan nozzle and don’t turn up the pressure. As a general rule, if the pressure is too high to touch then it’s too high for the deck.

Ahead we’ll go over some tips on how to properly pressure wash your Trex decking and preserve its appearance.

How To Use A Power Washer On A New Trex Deck

Before we get too far into the article I recommend you contact Trex or your Trex dealer before power washing your deck to make sure it’s safe on your particular decking. Trex is always coming out with new product lines and may make adjustments to older ones. When in doubt stay on the safe side and double check.

Whenever you use a pressure washer to wash a Trex Deck, use a fan tip and low pressure. High pressure can damage just about any surface including decking. If you damage your deck with high pressure it’s irreversible and will void the warranty so keep the pressure very low. I like to keep it in the 500-600 PSI range.

If you need more pressure raise it slowly and use a test piece. I always like to test out higher pressure on a scrap piece of decking first to see what it’ll do to the decking.

Below are a few simple steps detailing how you can safely pressure wash a new Trex deck.

Use a washer with a fan attachment and pressure around 1500 PSI. (Trex says you can use up to 3100 but I never go that high.)
Wash the deck with simple soap and water and scrub with a soft bristle brush. This will loosen stuck on dirt and grime that can later be washed off with pressure. Only use approved commercial cleaners if soap and water doesn’t work.
Remove dirt, mold, mildew and grime with the pressure washer after you wash and scrub. The nozzle should be held at least 8 inches away from the deck at all times.
Rinse the deck afterward. Don’t leave dirty water sitting on the deck.

If you hold the nozzle too close or use too much pressure you could damage the deck.

If you leave residue or dirty water it could cause fading and/or discoloration.

When Not To Use A Pressure Washer On Trex

Unfortunately, not all generations of Trex are safe to power wash. It’s very important to determine what generation of Trex you’re working with before using a pressure washer on your deck. Older Trex models can be damage by even low amounts of pressure.

The following is a list of Trex generations that are not compatible with pressure washer cleaning.

Accents
Origins
Brasilia
Profiles
Contours

Using a power washer with these earlier generations of Trex is not recommended because it may cause damage. The use of a power washer with these generations of Trex will void the warranty. If your not sure what generation of Trex you have then don’t use a power washer.

Some signs that you may have an earlier generation of Trex are staining, flaking or fading. This occurs because the old Trex material is not as durable or resilient as the new Trex generations.

Newer generations of Trex are more resilient due to an innovative, high-performance shell that’s wrapped around the surface of the boards. The absence of this protective shell on older Trex generations makes pressure washing them a bad idea.

If you’ve got an older model Trex deck use more traditional cleaning methods like soap, water and a soft scrubbing brush. If you try a commercial cleaner make sure it’s approved for your generation of Trex.

Can You Power Wash An Old Trex Deck?

Trex does not recommend power washing older generations of Trex and states it would void the warranty. And I don’t recommend it either. But can you do it?

A power washer could be used on an older generation Trex deck but it’s risky and could damage the decking. I’ve actually done it before but with power no greater than a garden hose. I would not use a power washer with any real pressure. If you want to use it on the lowest setting as a substitute for a garden hose then that would probably be fine but don’t turn up the pressure.

The reason I used it i because I like the fan head. If you have a similar head for your garden hose then use that instead but if not then a power washer will work. But again, don’t use pressure.

Older generations of Trex decking doesn’t have the protective outer shell that new models have. Because of this the decking is easier to damage.

When in doubt stick with soap and water with a soft scrub brush. It’s the best way I’ve found to clean a Trex deck of any age. If you need more cleaning power then try a commercial cleaner that’s approved for your generation of Trex decking.

Don’t assume that just because a cleaner says it’s OK to use on Trex that it means your Trex. Make sure it’s for your specific generation because they’re are big differences between new and old Trex.

Is Trex Easy To Clean?

There are lots of advantages to installing Trex decking instead of traditional wood. Trex is resistant to insects, rot, flaking, staining, and is made from 95% recycled materials. It’s a fantastic product that’s covered by a good warranty. And it’s easy to keep clean, especially when compared to wood.

Wood needs to be cleaned regularly and generally needs to be sealed and treated. That’s not an issue with Trex. Other than cleaning it’s totally maintenance free.

When it comes to cleaning my Trex deck, I like regular dish soap and water with a soft scrub brush. There’s really nothing to it. I wash the deck just like my floors and then rinse the entire deck off with a power washer.

I don’t use the power washer to clean for me, that’s done with the soap and scrub brush. But if there’s some stuck on dirt I can’t get off the power washer will do the job. It’s rare but sometimes I need a little more pressure to clean with.

The Bottom Line

Can you use a power washer on a Trex deck? Yes, if you have a newer generation Trex decking. And no,if you have an older generation. So make sure the first thing you do is determine what type of Trex you’ve got. But should you use a power washer?

Assuming you have the necessary equipment and a new generation Trex decking that’s safe to power wash, using a pressure washer can provide a good cleaning for your deck and keep it looking brand new for many years.

I look at Trex deck cleaning and maintenance as a comprehensive approach. A pressure washer is fine if you really need one but I use them as a last resort. My first step is always a wash with soap and water and a good scrub. After all, these steps are necessary when you use a power washer anyway. I use my power washer more as a final rinsing then as the main method of cleaning. My soap and scrub brush do that.

I can’t stress enough how important it is to use low pressure, a fan nozzle and a distance of at least 8 inches from the surface. Too much pressure or keeping the nozzle too close to the deck can damage it.

Before I use a power washer I always test it on a scrap piece of decking. It’s a great way to know exactly what the power wash will do to the decking. If you have a new deck it’ll be easy to get some scrap from just about any Trex dealer or even Trex themselves. It’s worth the time and effort to make sure power washing is safe.