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Why The Roof Cleaning Chemicals Can Kill Plants

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Ok, all roof cleaners know that plants must be protected from the run off, or they can die. But have you ever wondered WHY or HOW the chemicals we use can kill plants ?

Well, I did, and so I set out years ago to find out how and why our roof cleaning chemicals killed unprotected plants.

Here I am, back in 1999, asking this very question, on a forum where you can get answers from people who really know what is going on. http://www.madsci.org/posts/archives/jul99/932670591.Bt.q.html

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PeakofPerfection had a post talking about using Gypsum to bond with the sodium in the chlorine turning it into calcium and sulfur. I don't know how fast this reaction takes place (or the validity of this reaction) but could it possibly be used in some sort of bag attached to down spouts to remove the need for catching excessive chemicals that come out when rinsing? 

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Fortunately in my mid-west area nearly all houses have gutters so it's not much of an issue although we still must be careful. I did a large house a few weeks ago that surprisingly did not have gutters and that was a first for me. We took the needed care to ensure minimum run-off and that any landscaping was adequately watered.

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Fortunately in my mid-west area nearly all houses have gutters so it's not much of an issue although we still must be careful. I did a large house a few weeks ago that surprisingly did not have gutters and that was a first for me. We took the needed care to ensure minimum run-off and that any landscaping was adequately watered.

 

Dave, you don't worry about collecting any run-off from the down spouts? I'm always worried that it could burn the grass around it. Here in KY the vast majority of houses do have gutters too.

 

David Smith

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Gypsum, sold at the big box stores as a soil conditioner, also counters salt in the soil.  This is just part of the risk mitigation process.  (Many overlook the potential salt damage).  And yes, absolutely capture ALL SH/mix at the down spouts.  Grass is the least concern as sod is cheap.  But that $4000 weeping Japanese lace maple is another story........  If you think burning a few leaves with mix is bad, wait until it systemically absorbs some SH.....  The leafs will practically jump off of that tree.

 

Ensure the gutters are pitched properly, otherwise you potentially leave GALLONS of mix in the gutters just waiting to create problems during an afternoon storm..  Flush if/as applicable.  (Search for and make a 'gutter cane' for this purpose).

 

Anyone can spray this stuff that we use on roof.  Doing it responsibly and taking complete responsibility for one's action's commands a premium in our market.

 

Gypsum, charcoal etc to instantly neutralize the mix is futile, as it requires HUGE amounts of product to make any difference at all.  Sodium thiosulphate, although effective for the chlorine component, substantially adds to the sodium (salt) risks.  You simply trade one potential problem for another.

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Gypsum, sold at the big box stores as a soil conditioner, also counters salt in the soil.  This is just part of the risk mitigation process.  (Many overlook the potential salt damage).  And yes, absolutely capture ALL SH/mix at the down spouts.  Grass is the least concern as sod is cheap.  But that $4000 weeping Japanese lace maple is another story........  If you think burning a few leaves with mix is bad, wait until it systemically absorbs some SH.....  The leafs will practically jump off of that tree.

 

Ensure the gutters are pitched properly, otherwise you potentially leave GALLONS of mix in the gutters just waiting to create problems during an afternoon storm..  Flush if/as applicable.  (Search for and make a 'gutter cane' for this purpose).

 

Anyone can spray this stuff that we use on roof.  Doing it responsibly and taking complete responsibility for one's action's commands a premium in our market.

 

Gypsum, charcoal etc to instantly neutralize the mix is futile, as it requires HUGE amounts of product to make any difference at all.  Sodium thiosulphate, although effective for the chlorine component, substantially adds to the sodium (salt) risks.  You simply trade one potential problem for another.

Thank you for your expertise Ted. I will be picking up some gypsum to keep on hand in the case of a spill. It sounds like collecting SH at down spouts is the most effective (and necessary) way to protect landscaping.

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PeakofPerfection had a post talking about using Gypsum to bond with the sodium in the chlorine turning it into calcium and sulfur. I don't know how fast this reaction takes place (or the validity of this reaction) but could it possibly be used in some sort of bag attached to down spouts to remove the need for catching excessive chemicals that come out when rinsing?

I don't think that would be practical and I don't think the reaction is that fast. Plus at $8 per bag, it could get spendy. But keeping a pail of it onboard for application around areas that may get runoff definitely is a good idea and we now practice it. Just get a 5 gal bucket with a lid and a few 50 lb bags plus a scooper. Keep the bucket and scooper on the truck and apply as needed. Your first and best defense is to control your runoff, followed by lots of watering. The Gypsum is your third line of defense and is good for placement below downspouts that don't go into drains after dilution.

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Dave, you don't worry about collecting any run-off from the down spouts? I'm always worried that it could burn the grass around it. Here in KY the vast majority of houses do have gutters too.

 

David Smith

David, you misunderstood me. My point is that since almost all our houses do have gutters and hence downspouts, we don't have to worry about run-off and do use bag collectors on the downspouts.

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For those that don't rinse, don't forget about the sodium left on the roof,after the chlorine has flashed off. It has to go somewhere and that somewhere is the foliage when it rains and the gutters dump onto the plants.,

Also, if the gutters go into drains, don't just assume things are hunky dory. If the drains go into an adjacent protected wetlands you are still on the hook. Always be aware of where your runoff goes.

The vast majority of the time, our product and process is safe and dilution and things like Gypsum help offset most risks. As Dave stated, it is how you deal with the effects which sets the professional apart.

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I don't think that would be practical and I don't think the reaction is that fast. Plus at $8 per bag, it could get spendy. But keeping a pail of it onboard for application around areas that may get runoff definitely is a good idea and we now practice it. Just get a 5 gal bucket with a lid and a few 50 lb bags plus a scooper. Keep the bucket and scooper on the truck and apply as needed. Your first and best defense is to control your runoff, followed by lots of watering. The Gypsum is your third line of defense and is good for placement below downspouts that don't go into drains after dilution.

I knew a roof cleaner who used to leave collection bags attached to the downspouts, but he went one step further! He actually added some sodium thiocynate powder to the bags, and some Gypsum, LOL

That way, when the run off hit, it was neutralized, but he never planned for the HEAT of the neutralization reaction! 

LOL, he said it melted the freaking bags :)

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I knew a roof cleaner who used to leave collection bags attached to the downspouts, but he went one step further! He actually added some sodium thiocynate powder to the bags, and some Gypsum, LOL

That way, when the run off hit, it was neutralized, but he never planned for the HEAT of the neutralization reaction! 

LOL, he said it melted the freaking bags :)

Talk about "burning the grass"! "Sorry Sir, your roof is clean but we kinda melted your downspouts". 

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Here is a better way without toxic chemicals... https://www.youtube.com/watch?v=aCWH1z32zRE

 

Welcome to the RCIA Chris :)

 

In this video of yours you talk about "Chlorinating The Roof", yet in another video, you talk about how bad Chlorine is ?

 

 

What you are doing is nothing new my friend :)

 

And, it has it's place perhaps, on a Tile Roof.  However, I have my concerns, on a shingle roof, because of potential granule loss.

 

Still, we all know that water alone will not kill all the algae spores, so it would seem to be best to follow up the cleaning with a spray of Borax and Water maybe, or even some chemicals from the Quat Family, for longer lasting results :)

 

Chris, perhaps you can offer, your cleaning only,.  for say 500.00 for a small tile roof, then, offer a roof treatment for 100.00 more, then, if they are big spenders, treat that roof with a Quat, for 200.00 more ?

 

Your way of cleaning is different from ours Chris, but it is always good to look at EVERY form of roof cleaning that there is.

Thank You for stopping by, and joining the forum.

 

Perhaps we can all learn something from each other :)

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Here is a better way without toxic chemicals...https://www.youtube.com/watch?v=aCWH1z32zRE

Read the roofing manufacturer warranties and cleaning recommendations. GAF, Owens Corning, Pabco, etc. In the video you talk about following the ARMA guidelines. So what do those guidelines say? From the ARMA website:

"Algae discolorations are difficult to remove from roofing surfaces, but may be lightened by applying a solution of liquid household chlorine bleach (sodium hypochlorite) and water. Directions for mixing solutions of these ingredients may vary among shingle manufacturers and depend on the amount of discoloration. A typical solution should be one part chlorine bleach and one part water. Other cleaning chemicals or methods should not be used without approval of the shingle manufacturer."

Okay a bit vague . So, What do the mfgs say?

Owens Corning warranty exclusions: "Damage to the Roofing System components caused by alterations made after completion of application, including structural changes, equipment installation, power washing, painting or the application of cleaning solutions, coatings, or other modifications."

Power washing is specifically mentioned, damage from applying cleaning chems too. If you are hitting the roof with pure Hydroxy...yeah. Typical roof mix will NOT harm shingles.

GAF: If a new roof is not an option, GAF recommends cleaning the roof with a special mixture. That mixture is: 4 gallons of water, 1 gallon of bleach and 1 cup of TSP (Tri-Sodium Phosphate-or acceptable phosphate-free substitute) found at many home centers. Apply this mixture with a garden sprayer, let sit on the roof surface for up to 20 minutes, and rinse with low-pressure water. Be sure to protect any shrubs below. Remember, the roof surface will become slippery when wet... be careful!!!

Do not power wash the shingles to clean the shingles. Some roof cleaning companies offer this service. However, it is not recommended as it may dislodge granules, which can lead to premature shingle failure.

This is pretty clear.

Pabco: The black stain that grows and spreads on a roof is typically algae. PABCO® recommends cleaning algae from your roof by killing it with an application of a 50:50 mix of liquid chlorine bleach and water. This is sprayed onto the surface of the algae with a low pressure sprayer, like a garden weed sprayer. Allow the solution to dwell on the surface (15 to 20 minutes) and then rinse thoroughly with low pressure water. Do not use abrasive cleaning methods such as pressure washing or the use of a brush or broom.

Again, pretty clear. But you are not power/pressure washing, you use 500 PSI! You are not pressure washing! Really? What would an attorney say? He/ She would ask Are you utilizing pressurized water at a high enough PSI to remove the visible algae layer and remove the discoloration from the shingles? If yes, you are pressure washing. No jury eould find otherwise.

Will that method kill the organism to prevent potential rapid re growth? No. From a mycological approach...valid because GM is spore based....no. It is akin to wiping off the surface fruiting bodies from a mold infestation. As the owner of a Mold mitigation company for 14 years, I can tell you it is invalid. Is this method a good business practice? From a repeat business standpoint, heck yeah. From a roof cleaning and value added basis....questionable if SH based cleaning lasts much longer.

Is chlorine harmful as a discharged waste? The EPA says no in typical household concentrations which a typical roof mix is. What is chlorine bleach and how do you make it? Saltwater plus electricity. What happens to it after it degrades? It degrades back into Salt water. Can the environment withstand the discharge? It is ultimately a materials neutral cycle on a global basis, salt water to salt water. On a local basis could it spike salinity? Yes with improper discharge handling. Are selected capture of runoff and dilution effective? Yes as return trips to the treated propert years after prove. Does high power wash water usage spike salinity in the Florida environment? I'd argue Yes. By drawing down water tables thru far higher water usage in comparison to limited SH cleaning based water use. Does cleaning with SH limit waste water discharge in comparison to pressure washing and soft washing? Yes. Can excess water discharge from power washing cause issues? Yes, which is why reclamation is mandated in many communities. Are you reclaiming your discharge per local regulations? Unknown.

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I like one of the other videos where we see a tile roof being cleaned with a caption that reads as follows,

 

"Chemical roof cleaning kill plants!"... Yes thank you captain obvious. If you do some research on roof cleaning you will learn that it is in fact a plant on the roof surface. Therefore killing the plant is the goal in roof cleaning. As opposed to just rinsing some of it from the surface with water.

 

"Does NOT remove dirt/debri"... Well that doesn't really apply to roof cleaning since dirt/debri are not the main cause of the black coloration of a roof. Again its a living plant on the roof surface.

 

"It bleaches the color of the tile and your roof look faded!"... Along with the bad wording, this statement is false. Every roof I've ever cleaned with chemicals went back to its natural color and a faded tile roof is caused by high pressure washing year after year removing a layer from the surface each time it is cleaned

 

"Rots your base sheet"... How does it reach the base sheet?

 

"Corrodes your metal"... What metal?

 

 

 

Not a smart idea to show up on a non pressure roof cleaning forum and say here's an alternative to toxic chemicals when in one of the videos you have a yellow 2.5 gallon jug next to your pressure washer. The exhaust from that machine is also toxic but you don't run it in your house and breathe in the fumes now do you. Although maybe you should try it and let us know how that goes for you.

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Perhaps a better plan would have been "Hey Guys, I clean roof this way, vs your way, so let's have a good heated debate on what way is best".

But, when you come on a Non Pressure Roof Cleaning Forum, with preconceived notions, that is not, IMHO, being open minded.

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