Trex* I have a Trex deck 3yrs old and it has black spots in the areas of full sun.?

Question

What is this? How do I fix it? I power sprayed it in the spring, but the black spots are back.

Answer 1

You better call the company where you got it. Sounds like a manufacturing defect unless something got spilled on it an it has molded.

Answer 2

black molds from the bark and stems of the trees or from the molds in the bark mulch in the nearest flower beds mix half and half house hold bleach in a garden sprayer and add a drop or squeeze of palmolive or any glycerine detergent then spray aand brush or broom then keep it wet with a hose as you scrub then after the molds are eradicated final rinse then maybe think about armour all on the entire surface before winter its vynyl right just lightly because it could become too slick and dangerous

Answer 3

Mildew grows on everything, even rocks. If you spray a mild mildewcide on it (like a diluted lithium hydrochloride) solution, it'll kill it. Virtually everything is a home for mildew, I don't necessarily think it is a defect.