Pressure Washing a Trex deck

[nbpt100]

I pressure washed a Trex deck that is under a tree and was filthy from well over a year of neglect.

I did not use any soap. Just plain water. It came out ok but not a clean as I thought it would. It still has some stains that appear to be ground in dirt. I tried scrubbing with a brush and some Simply Green and it did not effect anything. If I go too aggressive with the pressure it will damage the decking. It can be a difficult balance.

Is there a simple and safe way to clean up this ground in dirt. I don't like to use aggressive chemicals as they can do a number on grass and gardens....not to mention the person using it.

Thanks

 

[LXCam]

Mine has cleaned up fine with SG and a lite brushing so far. Hopefully you find out what will work better cause I don't have any suggestions.

 

[Jeff95TA]

Are you talking about the old style Trex composite (vs. the new wrapped style)? I used Olympic premium deck cleaner, the plain old stuff you can find at Lowe's. That's the recommended type of product. It did surprisingly well with no scrubbing and even better with some scrubbing and a low pressure hose to rinse.

 

[ford33]

I have an older composite Trex deck. The spots you are seeing will not go away. I have tried multiple products over the last 16 years and have had little success. Best solution is a deck cleaner, a stiff brush and a pressure washer with wide angle nozzle. Bleach will help remove the mold.

The spots are not ground in dirt but a discoloration in the product caused by mold. The bleach will kill the mold and lighten the spots but it will return within a few weeks and the spots will darken and remain visible.

Trex was sued but won the lawsuit.

You must clean the deck every year.

 

[nbpt100]

Mine has cleaned up fine with SG and a lite brushing so far. Hopefully you find out what will work better cause I don't have any suggestions.

What is SG?

Are you talking about the old style Trex composite (vs. the new wrapped style)? I used Olympic premium deck cleaner, the plain old stuff you can find at Lowe's. That's the recommended type of product. It did surprisingly well with no scrubbing and even better with some scrubbing and a low pressure hose to rinse.

I am not sure but it looks newer. The bottom side is a different shape.

I have an older composite Trex deck. The spots you are seeing will not go away. I have tried multiple products over the last 16 years and have had little success. Best solution is a deck cleaner, a stiff brush and a pressure washer with wide angle nozzle. Bleach will help remove the mold.

The spots are not ground in dirt but a discoloration in the product caused by mold. The bleach will kill the mold and lighten the spots but it will return within a few weeks and the spots will darken and remain visible.

Trex was sued but won the lawsuit.

You must clean the deck every year.

Do you recommend any particular deck cleaner?
Thanks.

 

[LXCam]

SG-simple green.

 

[nbpt100]

OK...I went on the Trex website....I don't know why I did not think to even look there until tonight.

The have two recommended cleaning processes depending on the Trex style. The older style as mentioned by Jeff recommends using Olympic Premium Deck cleaner or Expert Chemical Composite Deck Cleaner. The Olympic is mostly bleach from what I can gather from reading about it. One person said mix 1 quart bleach with 3 quarts water and a cup of powdered detergent and it will do the same thing. I don't know but it sounds plausible. they say do not pressure wash this style of Trex. You just rinse the cleaner off with a garden hose.
For The newer Trex they say to only use soap.....no specifics.....in an instructional video it shows the person adding what looks like dish soap in to the bucket. They say you can pressure wash the newer style but use a fan pattern and do not use a machine that can produce over 3100 psi. Perhaps the bleach is too strong for the newer style but the pressure washer <3100 psi is fine. I am not sure how to identify the style of this composite decking. Any ideas? The deck is only one step off the ground. So I cant view any markings that their may be on the back side. So what happens if you use bleach on the newer Style....I guess it will discolor.
LXCam: did you dilute the SG? Also can I assume you have the newer Trex style?

 

[ford33]

Old Trex is one color and has no "wood grain appearance wrap" around the board. It doesn't look like wood but has a brown color but no wood grain appearance.

I used Home Depot Behr deck cleaner to clean my deck. I added a small amount, less than a 1/2 cut to a gallon, of bleach. Careful to not add too much bleach.

 

[nbpt100]

Old Trex is one color and has no "wood grain appearance wrap" around the board. It doesn't look like wood but has a brown color but no wood grain appearance.

I used Home Depot Behr deck cleaner to clean my deck. I added a small amount, less than a 1/2 cut to a gallon, of bleach. Careful to not add too much bleach.

OK this is light Grey in color, if it is in fact Trex, it must be the newer style.

Update: I contacted Trex and they told me you can use the Olympic Premium deck cleaner on either the newer or older style. They said just rinse it very good. This makes it a mute point as to which style it is and what cleaner may be best or acceptable with out doing any damage.
Thanks to all.