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MJ · Nov 14, 2011

Feedback appreciated on remaining mysterious stains?

Roof Cleaning Tallahassee · Guest

Was the downspout clogged? Looks like the gutters have been overflowing at the corner and hitting that area of the roof below for quite some time. What was the tempeture when you layed down your mix? I use fresh (hot) SH and never applied any that was six weeks old. Some of the other guys here that buy in bulk could answer the SH breakdown over time question better than myself.

Roof Cleaning Cleveland (216) 323-0552 · Nov 14, 2011

If I'm using old sh I'll bump it to about 50/50 and see what happens. The last roof I cleaned was an older roof and the granuals were worn away where the downspout from the upper roof drained on the lower roof. Other than that you need to look at the roof when you're done and if it's not all clean re-do the dirty areas.

Guest

looks like missing granuales

MJ · Nov 14, 2011

The downspouts were not clogged, the stain over the garage where the ridge vent and weather vane is the HO's issue and mine, given the fact that there is a stain on back/south side, where there were no algae just makes me wonder why is it running in line from the weather vane on the ridge. if it was only on the front, I would say hotter stuff, 3rd pass, SH is very hard to get in our area, and fresh SH this time of the year is even harder to find. I have had some second passes, and but never had a third pass on algae, this would be my third pass. All of the other stains on the roof have went poof, gonzo.

We have had record rain fall in Cincinnati. The lichen is very stubborn when protected by trees and overhangs. Thanks for your feedback, I will hit it again, and again. Need to make this client happy.

MJ · Nov 14, 2011

Before Pic. This time of year is is hard to get good pics with the low sun. This pic shows some stains on the higher roof.

Nov 14, 2011

I don't think its the mix, you said the stain runs down both sides of the garage roof from the weather vane correct? If you can get better photos of stain from the top both sides, also photos of the base of the weather vane, I would like toi know how it was installed.

MJ · Nov 15, 2011

I'm going to give it a few more days before I go back out, need a few days of NO RAIN, I just feel there might be more going on here than the typical GCM and roof scum that we see, weak stuff is what I have right now.The back/south side just makes me think outside the box a little.

Nov 15, 2011

I have seen that type of stain many times up my way. The only time I see it is under a skylight, running perfectly as wide as the skylight down to the gutter. It looks Like G.M. but it's not, and you better spot it before doing the job...under the skylight is easy but yours looks harder to spot. You see under the skylight is usually GA free since the rain runs around the skylight. After much research { asking roofers and contractors } I was told it probably was caused by the sealer used around the skylight or tar and possibly even kerosene used to clean up the area after instalation of the skylight. So I am wondering if the instalation of the weather vane would fall into that possibility. Always investigate any stain that is in the exact same spot on both sides of the roof even if it looks like plain old G.A. be very afraid if one side is clean except for that stain. Remember to inform the home owner that you " remove the Parasites " if you see that stain again always mention it's " a possibility " that it may not come out, usually you will still get the job and if you don't it's some one elses headache.

Roof Cleaning Missouri 417-230-8103 · Guest

MJ wrote:
I would appreciate anybody's feedback on the attached photographs. I will post a few before pictures just to show what presented itself when we orginially cleaned the roof and gutters. The two additional pictures at the end will show what is remianing. The case was a 20 year old roof, heavily wooded lot, with some of the nastiest gutters I have ever seen on a house. The roof stains looked normal and the lichen and moss was plentiful. It was a mid 60's day for cleaning with plenty of sun. SH was about 6 weeks old, a little on the downside. Our mix was 35% with our normal ammox M, no alcohol.
Homeowner was most appreciative of our services, however said, a few of the stains still remained. We said we would glady come by and re-treat the areas that he noticed. We found a very large discoloration and some burned out lichen and moss that was hanging on. Additional stains around the gutters that were just dark in nature. It really did not look like algae to me. We treated with a spray bottle 50/50 and as in the past, we thought this job was completed.
We visted the site a week later and took these pictures. The discoloration was still present.
My question is, is this due to the roof vent, the weathervane, or could we have caused any of this with our mix, or was it just under the algae stains all along? Has the metal in the roof vent caused this? Its on the south and north side of the roof.

Mike, It looks like weak mix, when temps start lowering remember to go back to using TSP, this will help beef up your mix.

One more thing , when you post pictures, please do not paste them in the thread, it streaches the form out , use the attach file button, I fixed this thread for you..

Make it a great day

Dave

Apex Roof Cleaning · Guest

I was using 2.5 month old Sh on my first couple jobs, all of them took 2 passes. I got some fresh stuff, and on my next roof, 1 shot and looks great. If the roof is truly facing north, that south side shouldn't have anything on it, unless it's recieving, moisture from that vent.

Dirty

MJ · Nov 22, 2011

Hitting it on Friday, Have fresh SH, will report back, thanks for the feedback.

Nov 26, 2011

Any update on this situation?

MJ · Nov 28, 2011

MYSTERY SOLVED! RE: Feedback appreciated on remaining mysterious stains?

Nov 28, 2011

RE: Feedback appreciated on remaining mysterious stains?

Maverick Contracting · Premium Member Roof Cleaning Institute of America

If they are still there, you can use a weak acidic solution to remove the rust.
Offer to take down the vane if not wanted and make sure to fill screw holes with caulking or tar

Apex Roof Cleaning · Guest

Ya i have the same question as long island. If I was a HO and you told me your softwash system could clean my roof, i would want the black rust stains to be removed as well. If it came clean, how did you do it.

Maverick Contracting · Premium Member Roof Cleaning Institute of America

Hehe posted at the same time Dan, acid removes rust stains read up

Tom C · Guest

So it was rust, that brings up a question, does anyone put a disclaimer in their estimate stating only certain stains will be removed, such as GM, lichens & moss but rust stains will not be removed? I haven't seen much on the forum about rust stain removal and I'd be leary of applying an acidic solution to comp shingles. If you do put a disclaimer in, what are some other stains that should be noted?

Nov 29, 2011

Tom I make notes of any possible stains like rust, also I look for " soot " stains from the chimney which will not come out. I let them know that I kill and remove the " parasite " only. I know guys have alot of luck with rust removal but for the couple hundred bucks I am not risking anything. Plenty of roofs around without major problems.

The Roof Cleaning Institute Of America Training & Certification Forum "Find A Certified Roof Cleaner Directory"

The Roof Cleaning Institute Of America Training & Certification Forum
"Find A Certified Roof Cleaner Directory"