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RE: Do weaker roof cleaning solutions keep roofs cleaner longer ?

Mar 23, 2013

Apple Roof Cleaning Tampa FL (813) 655-8777 wrote:
Bergman Roof Cleaning Port Charlotte FL 941-698-1959 wrote:
I understand. While the higher SH level in a cleaning mix cleans faster, it does not have the PH level to destroy the disease-causing organisms. The lower SH level, with more water, cleans slower but has more ability to destroy the disease-causing organisms.
While I understand the explanation, I would like to put it to a test. :)
The reason is, I do a number of small HOA developments -I mean small ones, like up to 15 houses on a circle drive etc. When I do 5 in a row one year, 2 years later, the one in the middle , or whatever, may be showing some small amount of algae growth, while the other 3 or 4 may look like I just did them.
So, I have come to see that even 5 tile roofs in a row are not going to stay clean the same length of time, even when cleaned with the same 45% SH mix used on them all.
Interesting facts and thought though!
At weaker levels (more water in the mix) the PH drops because of all that water. As PH drops in chlorine, the hyperchlorus begins to dominate. This is the disinfectant part of the chlorine, and one reason we add acid to swim pools, to drop the PH and disinfect.
At higher PH levels, the hypochlorite Ion appears, and that is what cleans for us. Weaker roof cleaning mixes have BOTH the acid and the hypochlorite Ion in them!
Strong roof cleaning mixes have only the Hypochlorite Ion, and little to no hyperchlorus acid to kill the algae spores.

This is why when you preventative spray to treat a roof, you only want 20 percent SH to water, and maybe add a little sulferic acid to the mix, but got to be careful not to drop the PH too far, or deadly fumes will form.
Unless one knows what is really going on with the SH, it does not make sense that a weaker mix can kill algae spores better.

Here's an idea Chris, tell me what you think.

Here in Greensboro, NC our city water has a ph balance of 8. My shingle strength mix using 35% of 12.5% SH with detergents/surfactants will give my solution a final ph of about 11.

Instead of using city water (ph 8) and adding sulfuric acid to drop the ph (I would be afraid to use acid this strong).

Start with a lower ph water to begin with. Rain water has a ph of 5.6 and would bring the ph down more to give your mix more disinfecting power.

http://en.wikipedia.org/wiki/Rain

Since tile roofs take longer to clean with 35% and 50% strength does not last as long, perhaps a 40% mixture using rain water instead of city water would be faster and last longer?

-- Edited by Roof Cleaning Pro Greensboro NC (336)362 7659 on Saturday 23rd of March 2013 12:07:21 PM

RCIA Founder

Roof Cleaning Pro Greensboro NC (336)362 7659 wrote:
Apple Roof Cleaning Tampa FL (813) 655-8777 wrote:
Bergman Roof Cleaning Port Charlotte FL 941-698-1959 wrote:
I understand. While the higher SH level in a cleaning mix cleans faster, it does not have the PH level to destroy the disease-causing organisms. The lower SH level, with more water, cleans slower but has more ability to destroy the disease-causing organisms.
While I understand the explanation, I would like to put it to a test. :)
The reason is, I do a number of small HOA developments -I mean small ones, like up to 15 houses on a circle drive etc. When I do 5 in a row one year, 2 years later, the one in the middle , or whatever, may be showing some small amount of algae growth, while the other 3 or 4 may look like I just did them.
So, I have come to see that even 5 tile roofs in a row are not going to stay clean the same length of time, even when cleaned with the same 45% SH mix used on them all.
Interesting facts and thought though!
At weaker levels (more water in the mix) the PH drops because of all that water. As PH drops in chlorine, the hyperchlorus begins to dominate. This is the disinfectant part of the chlorine, and one reason we add acid to swim pools, to drop the PH and disinfect.
At higher PH levels, the hypochlorite Ion appears, and that is what cleans for us. Weaker roof cleaning mixes have BOTH the acid and the hypochlorite Ion in them!
Strong roof cleaning mixes have only the Hypochlorite Ion, and little to no hyperchlorus acid to kill the algae spores.

This is why when you preventative spray to treat a roof, you only want 20 percent SH to water, and maybe add a little sulferic acid to the mix, but got to be careful not to drop the PH too far, or deadly fumes will form.
Unless one knows what is really going on with the SH, it does not make sense that a weaker mix can kill algae spores better.

Here's an idea Chris, tell me what you think.
Here in Greensboro, NC our city water has a ph balance of 8. My shingle strength mix using 35% of 12.5% SH with detergents/surfactants will give my solution a final ph of about 11.
Instead of using city water (ph 8) and adding sulfuric acid to drop the ph (I would be afraid to use acid this strong).
Start with a lower ph water to begin with. Rain water has a ph of 5.6 and would bring the ph down more to give your mix more disinfecting power.
http://en.wikipedia.org/wiki/Rain
Since tile roofs take longer to clean with 35% and 50% strength does not last as long, perhaps a 40% mixture using rain water instead of city water would be faster and last longer?

-- Edited by Roof Cleaning Pro Greensboro NC (336)362 7659 on Saturday 23rd of March 2013 12:07:21 PM

The rain water would be great, except my girlfriend wants it to wash her hair with

Guest

Whether using a light mix works better or not is somewhat irrelevant. Use a "normal" mix and it will work as expected,.. and, as it weakens over the course of several hours you'll get to the lower Ph levels you believe will keep it clean longer. I personally think using a normal mix will take care of the problem, whether the aforementioned scenario plays out or not. Also, weak mixes are used for treatments because that's all it takes to destroy the little that is on there. Has nothing to do with killing the micro-spores or whatever.
Although I like the science of the washing business in general, there's only so far you can take something as simple as roof cleaning, and even house washing for that matter,..all though house washing will throw more scenarios at you than roof cleaning ever will.

Jeff

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