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What are the main ingredients the non-toxic algae/mold removers/preventers companies sell for shingle roofs? Is it just a basic non-toxic cleaner you can buy at any store or is it something different?
 

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I am a pressure cleaning contractor

I specialize in roof cleaning. What I have been using for years is sodium hydroxide(lye). Bleach works but not was well, plus I have heard it voids termite warranties and it also causes the shingle to curl up on the ends.
 

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Can any of these products be used on drywall/insulation? Does it take direct contact to work?
I am currently trying to save a wall that is almost 400 ft. long by 25 ft high. Exterior is concrete block with metal lath, fiberglass insulation and 5/8" drywall. So far I have black mold which has been resealed, grey, green and yellow molds as well, these have been left open.
BTW, my recommendation was to remove everything but I am between two national corporations and a very large landlord. THEY are the ones determined to save this wall.
Has anyone ever tried oxygen deprevation? Would it work? A few small holes and flood the space with Nitrogen or Argon. Just thinking outside of the box.
 

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I am not a fan of cleaning shingle roofs because they are granular and a power washer will wash away alot of granuals. I will wash cedar roofs, however.

I've done quite a few attic mold remediations. We usually use Clorox Biocide. It is a bleach with some agents mixed in to kill fungus and mold. This can be used as a typical cleaning agent to clean just about anything, but mix if 25/75 and it will kill just about anything!
 

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One more thing. Granual loss is commonly mis-diagnosed as fungus (black discoloration).

Shingles are made of asphalt, some asphalt with fiberglass reinforcement. Regardless asphalt is black and when your granuals start to wash away in high water traffic areas, it looks like stains, when infact it is a lack of granuals. Washing it, in that case, will only make those stains worse.
 

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Wrong

I am sorry but you are completely wrong. Ist pretty obvious if you had EVER cleaned a roof CORRECTLY that the cleaning removes VERY FEW granules. If you use too much pressure which is probably the cases(use around 500psi), of course you will damage the shingle. I have never seen a roof where it looks like fungus but is actually granule loss. The only way you could misinterpret this is if you were looking at it from the ground. If you cleaning a roof you will instantly be able to tell that it was a fungus you cleaning off, because the black "stain" fades away completely. I am curious about your method of cleaning wood shakes. You don't use high pressure on those too do you?
 

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"I" have never cleaned a roof but "I" have replaced many roofs that have been cleaned and damaged because of the cleaning.

"I" also have been called out to quite a few roofs where the home owners asked how they got all that algae and when "I" got ON the roof it was incredibly apparent it wasn't algae at all, and was really excessive granule loss.

Roof cleaning is something I am looking into offering as one of my services. I have come to learn that you want no pressure above 800 psi on the roof. While I have read many hours of literature at many sites, and even watched quite a few videos.... I am STILL not a fan of cleaning asphalt SHINGLE roofs. I do understand the cleaners do the cleaning and then you rinse the cleaners away. That's still not the point, as I have seen misdiagnosis and seen damage caused by cleaning of roofs.
 

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I am sure that you have seen damaged roofs due to cleaning, because anyone with a pressure washer thinks they can clean a roof. I have also seen many roofers in this area tell people that what is truely algae is actually the roof deteriorating and that they need to have the roof replaced. It sounds like there is someone in your area parading around as if they were a roof cleaner, giving us who make our living doing it a bad name. I don't mean to be antagonistic but I have to defend what I do when someone questions the processes or the purpose. If I were you I would find a roof I could test out what I have learned, find out what a difference it makes when you do it correctly and start marketing the hell out of it. Because it sounds like you have a eager market for someone who knows how to clean roofs. The best way to market for this service is to educate the customers and the whole process.
 

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vandiesel99 said:
The best way to market for this service is to educate the customers and the whole process.
That's exactly the founsation of all my sales. Educate the customer who not to do business with and what to look out for in unskilled or shady contractors and why they should pay more to hire me.
 
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Grumpy said:
Roof cleaning is something I am looking into offering as one of my services. I have come to learn that you want no pressure above 800 psi on the roof.

800 PSI?

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Roof-A-Cide is correct. Pressure at a water plant or near a tower should be about 80 PSI. Pressure is lost through use and time of day is the largest factor. More water is used in the morning and early evening, this is when you get your largest pressure drops.
 

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So my 3000 psi pressure washer set on high would be too much? How about a 3000 psi elastomeric spray rig? Would that be too much for applying the algicide?
 

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Sewell, house jacking isnt cool. Poor folks come home and their house is gone :(
 

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Aaron,
You ought to see the looks on their faces. No matter how hard you try to prepare them for it, when they get home from work, they still look like this: :eek: I love doing foundation replacements. Sometimes I think it's more for the fun, than it is for the money. :D

Aaron, you and I had a discussion a while back about cheap ba$tard General Contractors who mistreat their subs. Here's a good reason for not doing that: Last night, the contractor who has been doing my reinforced concrete work called to tell me that he just poured the footings for a $500,000 addition. The Owner is looking to dump his current GC, and wants to meet with me. I guess that my mason friend is happy about the way that I have treated him in the past.

Best wishes,
 

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Grumpy said:
500 psi is alot? Anyone know the PSI of a standard garden hose?
Yeah, 500 psi is a lot. Way more than I'd want to hit my shingle roof with.
 
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