Can this be washed? I don’t know this house material

This guy wants me to clean all the windows frames and sills but at the same time the house as well. I don’t know what type of material this is but is chlorine going to mess up this house siding. What do yall recommend I do on this or should I even take on this job. I use a water fed pole for the windows and then 12v pump for softwashing houses. I am just confused on what this material is and if it’s safe to wash
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