Need some help... streaks on paint.

[Bennyhonda 14]

I was powerwashing a townhome complex the last two days and when I went back to finish up the job today I noticed some streaking under the vinyl windows in an area that I'd already cleaned. It looked bad enough that I went back to that side and tried to brush out the streaks. They disappeared when wet but returned when dry.

The windows all have drainage ports at the bottom and this seems to be where the streaking came from. I thought perhaps it was from the bleach or dried soap scum but my mixture was pretty mild. For the second half of the project I decided not to even use bleach and cut the soap in half. I also rinsed, rinsed and rinsed some more. I even tried some dishsoap for one unit as a test but the same streaks are in all areas.

Is it possible this is just something I didnt notice when the building was dirty but had been there all along? Hard water stains, or something in the windows that could have caused this? I'm racking my brain but I'm not sure what to do.

My mix with the x-jet (open tube, no flow nozzles):

1st half: 1 gallon 6% SH, 3.5 gallon H20, Two scoops simple cherry

2nd half: One scoop simple cherry 5gl H20

Test unit: Approx. 6oz dishsoap, 5gl H20

Any help would be greatly appreciated.

Edited June 3, 2009 by Bennyhonda

[James 625]

The streaks most likely are from caulking that has bled down and has turned black. Some type of degreaser or butyl cleaner will work.

[Beth n Rod 1,279]

Sometimes, we are the messenger.

It could very well be an pre-existing condition that was only revealed after the wash process.

This could have been caused by someone else's process and now you are finding it out for the first time.

Since you brushed it, you ruled out oxidation but the other possibility is that it is aluminum oxidation from the window capping or some other reaction in the window area that is leaving this condition.

Post pics if you can.

Rod!~

[Bennyhonda 14]

The streaks are lighter in color. I'll try to get some pictures today.

Edited June 3, 2009 by Bennyhonda