Oxygen bleach is another option to consider.
Best way to remove mold and mildew from vinyl siding.
A popular homemade option is to mix three 3 parts distilled white vinegar with seven 7 parts water in a bucket.
Your standard household whitener.
It appears to make mildew vanish but on porous surfaces such as wood or vinyl siding chlorine evaporates too quickly to get to the fungi s roots guaranteeing regrowth.
8 apply a solution of trisodium phosphate dishwashing liquid oxygen bleach and water.
Avoid using chlorine bleach because it is harmful to vegetation.
Hard stubborn mildew or algae is tough to remove with only pressure washing.
If you prefer a commercial product mix one 1 part bleach with four 4 parts water.
On top of that you need a vinyl siding cleaner that fits with your pressure washer and does the cleaning with ease.
It will effectively remove mold and mildew from vinyl siding.
A chemical solution is necessary.