Streaking on Vinyl - HELP!

[oneness]

These are pics of a house I washed for a friend a couple months back. I just re-washed the heck out of it today to see if I could get rid of the streaking...I had assumed the streaks were un-rinsed soap (it is chalky, and comes off if you wipe your thumb across it), but it doesn't appear to be. What it looks like is oxidizing vinyl...I'm not even sure if vinyl does this. If I take a wet white rag and wipe the streaked areas, it comes off on the rag, and is the same greyish color as the siding.

The strange thing is that the streaks are in regular intervals, about 16=24" apart..I didn't think to measure while I was there. They're also not lined up with any particular part of the wall (seams, etc).

This wall is on the south side of the house, which gets sun most of the day, most of the year. That, in my mind, might explain the oxidation, but not why it shows up in streaks like this. The rest of the house is vinyl/brick, and the vinyl didn't do this on the other three sides.

I've never had vinyl siding do this, and I washed this house with the same soap/bleach mix that I always use. I tried a pretty strong wax mix (1/4 gallon in 5 gallons of water) and applied that with the XJet, to no avail.

It appears to come off, or at least look better, if I scrub with with soap and a brush (and I mean REALLY scrub). I'm hoping to avoid having to do this.

Is there a cleaner that will work in this situation, and can anyone give me some insight into why it looked like this AFTER cleaning, and not before?

 

[oneness]

Next pic.

 

[Bob Gates]

It seems the streaks are in line with wall studs. 16" or 24" spacing. South side as you know is Hot! It would seem that the two together (studs & heat) may be the culprit. I have never seen this before....Contact a vinyl company, installer etc. see if they can help.

 

[Larry L.]

I agree with Bob

 

[onecallpowerw]

It does not look to me like every stud. It seems in the photos they are too close together. Take a look at one full piece of siding. They normally come in 12' sections when new.

I would bet this is caused from the galvanized roofing/siding nails used to hang the siding. Oxidation from those nails will cause this. What I would do is pull a piece up and see if this is true. If so, not your problem.

 

[john orr]

I hate to be the bearer of bad news, but...Those are not streaks, they are caused by the nails used to apply the sheathing being super-heated, concentrating heat in one spot and "cooking" the siding. (Sometimes the nail gun isn't adjusted properly and the nails are not driven below the surface of the sheathing.)

There is no amount of washing that will fix this.

 

[Aplus]

I'm thinking it's caused from the weep holes in the siding. Look under the lip of the siding where the streaks are, and see if the little holes are there. Sometimes soap can get trapped in the holes and slowly leak back out.

 

[Mike Gwas]

I agree with Aplus, I think that is weep holes that drained. You may think I am crazy but try some HF acid on it.......

 

[john orr]

The photos don't show enough detail. I encounter this phenomenon on a regular basis, and I am telling you that the "streaks" are actually where the concentrated heat on the nail-heads has literally cooked the vinyl.

 

[oneness]

I'll see if I can get some better pics when it isn't so sunny...the streaks really don't show up very well in the pics.

I'll check the weephole thing too.

 

[Larry L.]

I agree with Bob and John

 

[Dale Walkowsk]

I think Bob, John, and Larry are right...if it was weep holes they would be more random...they seem to be in a line like studs.