Pressure Washing TREX?

I have original Trex, 12 yrs old and turned over some planks with charcoal burns. Obviously, the underside of these is considerably different than the rest of the weathered surface. Opinions are mixed whether to pressure wash or not. I would like to even out the appearance if possible. Any personal experiences out there with pressure washing, probably with a rotating tip and being as gentle as possible.

 

I don't know that I've ever had to clean Trex but if you are leery of using a pressure washer you can basically do the same thing scrubbing it with an old broom and rinsing with a garden hose. Bleach water is good for most cleaning including mildew, add TSP for stubborn grime.

 

I pressure wash my timbertech composite decking once or twice a year. I use the soap nozzle to apply an oxygen bleach based outdoor cleaner, let it soak a bit, and then pressure wash with a 30 degree nozzle. I've carefully compared the results with a leftover piece of decking that hasn't been washed and can detect no roughness or damage from the repeated pressure washing. I don't think I would use a narrower nozzle than 30 degrees though.

I'm not sure that cleaning the surface will get the planks to match though, as likely there has been some fading/color change due to UV exposure. Over time they will match better.

 

I don't think pressure washing will even out the color. You're dealing with fading so short of sanding down the surface to expose fresh, un-faded material I don't think there is much you can do. Mild/moderate pressure washing can remove dirt and debris but there is no chalk layer like with old paint to remove so I don't think it will do much to even out the coloring and if you get too aggressive you'll damage the surface of the Trex. I've even used Clorox Outdoor Bleach cleaning solution on my composite deck and there is no change in the color so I don't think you'll be able to bleach yours.

 

A PW will chip composite decking if aimed close enough and with enough PSI, especially the older trex. I would possibly use detergent and low pressure or a scrub broom and then PW only for the white vinyl rails if you have them.
Possibly shoot trex and email and ask what they suggest because abrasive brush/ PW/chemicals on the trex could open up the pores and make it weak.


I would just a little rub dirt into the brighter boards and then weather should make it all match decent enough over time.

 

This is composite so there are no pores.

I've used timbertech on my last 2 homes and have never had a need to use PW. Twice a year I use Olympic deck cleaner and it still looks like new.

PW composite if aggressive can dig into the surface and expose the wood fibers but just use caution.

Underside of the boards are not UV effected, they are facing down, but you will have some discoloration from dirt and water coming through the joints and staining.

You got nothing to loose by giving it a try, even if you put down new boards they will look different.

Decks and grills/fire pits dont mix!

 

Thanks for that astute observation on charcoal and decks. It only took me 12 years to move my Weber off the deck.

 

"This is composite so there are no pores."
well you know what I mean, I just meant 'pores' or into the grains etc. Composites aren't a solid piece of plastic, especially original trex.

 

I have a deck build with the original trex back in 1997, so it is over 20 years old now. It is still in really good shape and I pressure wash it once a year. My deck faces southwest so it gets a lot of sun and I think this is what keeps it looking the same with no real spotting or color issues. It is the original grey and people ask all the time if it is concrete - it is the same color as concrete. I don't use any soaps or anything to clean my deck, just pressure wash with water and it comes out really nice. My gapping is good since I put it up myself and the original salesman told me to gap it wider since it would swell. After 20+ years I am glad I spent the extra money on the trex because the maintenance is practically nothing compared to my dad's wood deck. He replaced his wood deck after 15 years due to splintering and warping of the wood and now has a composite deck as well.