vinyl siding red dirt stain removal?????

[jared brown]

I've been pressure washing for over ten years and i have encountered some siding i can't get clean. My soap is a sodium hydroxide mix that usually takes red mud stains "usually found near the ground" off vinyl siding with no problem downstreaming it.. This house has red dirt stains up high from the sofit down approx 2 feet. my thought is the house is near a dirt road and over the years road dust has settled on the siding, and gets washed off when it rains, but just below the eaves is protected from the rain and the dust doesn't get washed off. since i've washed the house the stain really sticks out against the really white siding i did get clean. i've put the soap on straight and brushed it and its still there. If you are not from georgia you probably can't understand how difficult it is to deal with red mud and red dirt stains. I've got to go back and do some more for my own satisfaction, anyone ever ran into this??????????and what did you use??

 

[clearview]

NC has the same problem. Never gotten it off before. I would try oxalic acid. Of course you'd want to make sure you've tested it somewhere out of sight first. I say that based on carpet spotting procedures for removing rust stains. Usually red clay comes out of carpet with degreaser type pretreatments. Something with butyl usually works on nylon. That's all the info I have about those stains.

 

[FCPWLLC]

Try some potassium Hydroxide. I had some luck with it and scrubbing with a soft brush.