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MJ · Oct 27, 2011

Stubborn stain question

Roof Cleaning West Chester PA · Premium Member Roof Cleaning Institute of America

definitely was a weak mix, loses its potency after 30 days ... if there are spots to touch up we use a pump up sprayer, just use SH & water though. looks like this might need more than a little touching up though?

also not sure what you mean when you say "hit with brush" and i never rinse a touch up

Roof Cleaning Severna Park MD · guest

I would not advise using a brush.. ever..

I've used a pump up sprayer before both to treat heavier stained areas and as a touch up tool.. I rarely have to make touchups on a different day anymore, but if it's not much, there's no problem using a pump up sprayer.

Roof Cleaning West Chester PA · Premium Member Roof Cleaning Institute of America

the more i look at it the more i think i'd probably take my rig out there ... unless it's just the picture, it seems that the entire area above the large window didn't come completely clean.

if the entire roof looked like that go over it again.

Maverick Contracting · Premium Member Roof Cleaning Institute of America

Just to note, some areas that may have been very bad may still look dark after proper cleaning if there was significant granular loss exposing the black asphalt making it appear still dirty but really its done damage. Had this at a customers house this past week just under where on gutter dumps onto the lower roof and got constant moisture. HO understood and was ok with it. Not sayin this is what is going on in those pics but is good idea to explain in advance to potential customers, do a visual check and if needed take an up close pic.

MJ · Oct 27, 2011

I'm sorry I should've posted the after pic. Here is the only one I have and its pretty far away but hopefully you can get a better idea. The first pic was the before picture.

Regarding the brush....I have seen a few pictures from others with a brush. We do not use a brush on any jobs however my only question was, when you get that stubborn one is it weak product or can the algae be "loosened" up for better penetration? I haven't used any alcohol in my mix just ammonyx m.

IMG_1982 (800x533).jpg

Maverick Contracting · Premium Member Roof Cleaning Institute of America

Mike what was/is the temp that you did the home? It might have been too cold. Temps around 50's solutions potency drops off a lot.

Roof Cleaning West Chester PA · Premium Member Roof Cleaning Institute of America

i use the same mix as you and we're in similar climates ... i'd never use a brush, i think i recall, and i'm not sure if it was on this website or somewhere else, somebody used a brush to remove moss after 2 weeks somewhere in the pacific northwest.

if you're loosening the algae with a brush, you're probably loosening granules as well ... once dead, a few rainfalls should do the trick ... you can also hit with a garden hose

MJ · Oct 27, 2011

Temp was in the high 60's but no sun

sweetwaterfish · Guest

Hit the problem ares with a pump-up at a 50/50 mix....problem solved.

Oct 27, 2011

Well two things,One- how did you leave the house when you took a photo still showing a problem? Two when I come across a very tuff stain and we are all wrapped up I will take the pump up sprayer....but I use full strength at this time. Full strength nips the problem in the bud right away and I can get out of there. When you see the stain go away after application throw some water up there { not alot just a little }because it was ful strength. Remember always walk around when your done checking everyones work, couple minutes extra beats going back.

Roof Cleaning Severna Park MD · guest

I would not have left if I still saw a heavy black stain over that window. Next time, mix 50/50 in a pump up and hit the trouble areas before you leave. A black stain will not rinse away on the next rain.

MJ · Oct 28, 2011

Thanks for the feedback, our sh was on the downside, and we pre-treated the hot spots, then hit the whole roof with foamer, then we re hit the spot over the window a 3rd time, only spot left on roof that IMG_1940 (800x533).jpg just so happened to be the most visible. Here is a pic of that was not visable from the ground, it was cleaned with our normal process. Funny how one small stain can cause a return visit, but the largest one's are elimanted in 1 pass.

MJ · Nov 4, 2011

Thank you getting back with me on their advice regarding touch-ups. Seems like with the cooler weather, we have been getting some more of these return visits in combination with my supplier older SH (about a month old at the last delivery). The uglies just aren't falling off like it did when it was 90 degrees this summer. Almost having to go back on almost 50% of the jobs right now. I guess the temp in the midwest here, might be playing a bigger role than I have encountered, this being my first fall in business. Strange thing is, some of the big ones come off and the small ones stay. One note about follow-up visits though is that customers love it and that they can tell we care about our results...I will post a few pics from that job now that is fully done. (Notice the bad stain is gone from above the far left window)

IMG_1956 (800x533).jpg IMG_2569 (800x533).jpg IMG_2575 (800x533).jpg

Roof Cleaning Cleveland (216) 323-0552 · Nov 4, 2011

Mike I would add less water.

Roof Cleaning Bradenton FL 941-822-2454 · Guest

Roof Cleaning Cleveland (216) 323-0552 wrote:
Mike I would add less water.

+1

Heat up the mix for sure, I have never left a job until the GM is gone. If you see problems after the mix has been on there for 20 min. it is your problem area, and your mix needs to be adjusted. I think kicking it up on the mix is better for the application then constantly hitting it over and over. More run-off to deal with.

I am not shy with the SH, cause I tested it with shingles and other roofing material, holds up very very well. Pre-treat the strong areas first let it sit then hit it again if need be.

Kim R

Nov 4, 2011

Kim makes a great point, Always do the darker- heavy moss/lichen areas first. This way when your done with the rest of the roof the initial area is ready if need be for a second hit. Less waiting around time.

MJ · Nov 4, 2011

Thanks for the feedback, did anybody notice the grass coming back from first pic to last one, about two weeks growth, we are doing a video shoot on Tuesday, weather permitting, the mix will be hotter, I have been at about 33%, and the stuff is now about 6 weeks old, so I'm going to go to 40% to 45% on next one, the HO has been killing her ivy around the landscaping for the last two weeks with Round Up, I told her that I could help her out with something that works better.

I guess the difference between 45 to 50% is really not that much when your talking about 50 gallons.

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