Art, the NP 9 I used on this job came from Brainerd. It cost me around $9 for surfactant on this roof, but saved me in SH and time. I'm going to give it shot on some regular roofs and see how it goes.
One has to wonder IF there is a difference in types and brands of NP 9 Surfactant ? The stuff from Florida Chemical Supply, at a mix ratio of 1 gallon surfactant per 100 gallons mix, is what made the roof cleaning paste in the pictures below.
Yours Barry seemed to have stuck really good, but I did not see this really noticeable film on the roof ? Maybe because your shingles were lighter in color ? We will have to see what happens when u try it on some darker shingles I guess ? Or maybe the stuff you get does not leave the film the stuff from Florida Chemical Supply does ?
The only way we can use NP 9 is to add it in on our last roof for the day. Our 325 gallon dual tanks can not be compromised with a non chlorine compatable surfactant. And make NO mistake, NP 9 WILL eat your chit, because the small amount of left over chemical we had from the church roof was totally useless in a few days!
But if you use the NP 9 right away, and mix right at the job, it can be a wonderful thing
Nothing in our experience sticks like it does, so far.
Plus, some customers seem to love the "Bio Film Barrier" it leaves behind, and all the wonderful bubbles and suds, as it comes off the roof.
In fact, I know someone who charges EXTRA for this "Bio Film Barrier", and gets good extra money for it too.
Chris, it definately leaves a film, I have noticed it when I stepped onto the flatter sections of this roof (very slippery, more than with my normal surfactant) and when I grabbed onto my ladder (you could feel how sticky the ladder rails were). I think your right, the lighter roof probably hid the film better than a darker roof would. I'll do some experimenting on the next few jobs and see where I'm at with using the NP 9 on a regular basis.
That's the hardest part of roof cleaning for me, remembering to take before pictures. I usually remember half way through the job, then I figure it's to late. I have plenty of AFTERS.
I have the same problem-forgetting pictures!
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