Algae stains on roofs

[hausdok]

I have a house that faces my yard, heavily wooded and the shingled roof looks like a green shag carpet with moss. All except the completely clear area directly under the skylight that is flashed with Copper, Clear and clean all the way to the gutters, probably around 12', hell the edges are even crisp like someone ran a lawnmower through it.

Comp or wood shingle?

Here I see that happening with shakes and wood shingle but not with comp. Here, it seems to work for 3 -4 feet and then peters out on a comp roof but will keep the roof clear to the eaves on shakes and wood shingles. I think it's got to do with absorbency; the wood cover absorbs the stuff leaching off the copper or zinc but the comp doesn't - at least not what I've been seeing here.

I suppose there can be different varieties of mosses and alga that are adapted to various regions that react differently. If there are, I can't imagine what it takes for a roofing manufacturer to reach an acceptable balance.

Still convinced the stuff does damage roof covers.

Bill, for the record, I hate roof cleaning companies. If I were King of the Planet, the state would issue home inspectors seasonal hunting licenses and allow them to thin out the roof cleaner herd once a year. Every inspector would have a 2-kill limit. Inspectors would be lauded as heroes for doing a service to humanity. [:-devil]

ONE TEAM - ONE FIGHT!!!

Mike

Bill;

I don't understand your hate for roof cleaners. What has any roof cleaner ever done to you for you to make the totally assinine and truly non-professional remarks that you made in this post. What puts home inspectors so far above roof cleaners that you think they should be granted the power and authority to "thin out the roof cleaning herd"? Is this just "ones man's biased opinion, or do you really have some kind of bone to pick with the roof cleaning industry?" Your comments could almost fall under "terroristic threatning" under the new laws. Perhaps you should give more "professional" thought to your comments before you make them. I really would like to know your "beef' with roof cleaners.

Care to explain?

Bill didn't write that; I did.

To answer your question; I'd say that's my biased opinion. It's mine. Not Bill's. I have a right to my opinions just like you have a right to your's. That's the wonderful thing about living in this country.

What's my beef with roof cleaners? Well, with very few exceptions, most roof cleaners I've seen have their heads stuck so far up their asses that I'm convinced they have to go to the proctologist to get their teeth cleaned.

If I had to guess at the ratio of properly cleaned roofs to improperly cleaned and damaged roofs that I see which have been "cleaned" by so-called "roof cleaners" I'd say it's something like 200 to 1.

What harm have roof cleaners done me? None, cuz if I saw one climbing up onto my roof with a pressure washer and that glazed deranged look in his eyes, I'd knock the ladder out from under him. Larry, Daryl and Daryl had better stay the hell away from my home with their friggin pressure washers.

Roof cleaners won't ever be given the opportunity to harm me, but from what I've seen, the majority of them seem to be completely incompetent. They don't harm me, they harm homeowners by ruining perfectly good roofs. Inspectors are in the business of inspecting homes and roofs and it's our unfortunate duty to have to inform people whenever we find a perfectly good roof ruined by some moron that gets a budgie every time he picks up his pressure washer.

Terrorist threat? LOL. You don't like the fact that I don't like 99.9999999% of roof cleaners; too friggin' bad - I'm a home inspector, I know all about getting dissed; and getting dissed hasn't killed me yet. Get over it or better yet, take your pressure washer and give yourself an enema.

ONE TEAM - ONE FIGHT!!!

Mike

[Bill Kibbel]

Hey Gary Wyer, Roof Cleaning Institute Of America Master Certified Roof Cleaning Instructor. I just read some stuff you wrote:

"Not taking care of roof algae can lead to increased home and cooling costs and will deteriorate the shingles".

Really - got any proof?

"It will begin to feed on the shingles and will spread over time eventually taking over the entire roof".

"...it is an airborne algae technically called Gloeocapsa Magma. It gets on the roof, survives by feeding on nutrients in the shingles, and is spread down the roof by rain creating the black streaks".

Bullshit. Gloeocapsa Magma is NOT an algea, it's a cyanobacteria. It does NOT feed on the shingles or nutrients in the shingles. See my post, #8 above.

[Greg Booth]

OP by hausdok....Roof cleaners won't ever be given the opportunity to harm me, but from what I've seen, the majority of them seem to be completely incompetent. They don't harm me, they harm homeowners by ruining perfectly good roofs. Inspectors are in the business of inspecting homes and roofs and it's our unfortunate duty to have to inform people whenever we find a perfectly good roof ruined by some moron that gets a budgie every time he picks up his pressure washer.

Terrorist threat? LOL. You don't like the fact that I don't like 99.9999999% of roof cleaners; too friggin' bad - I'm a home inspector, I know all about getting dissed; and getting dissed hasn't killed me yet. Get over it or better yet, take your pressure washer and give yourself an enema

....but can't you tell us how you really feel? [:-slaphap

[Steven Hockstein]

It seems to me that I am seeing staining more often now then in my earlier inspecting years. I have to assume one of two things:

1). The components used to make the shingles are different and less resistant to staining.

2). The stuff that is growing has become an epidemic.

3). Both of the above?

[KimR]

Mike,

I sent an email to you originally to discuss the roof cleaning that is discussed here. Just as thought some or many of you inspectors have came across rogue roof cleaners that used pressure on a roof. I am from a forum of roof cleaners that do not use pressure, we are very very against this, as you are. I had first found your site in google and could not understand why this guy cannot stand roof cleaners. I get it now, and totally agree that pressure should be never used on a roof and in reality should be minimal for many aspects of cleaning. There are many rogue roof cleaners that think you can rent a pressure washer from a big box store and have at it. This is unacceptable as it can cause a lot of damage to the roof's composition.As well as guys that pressure the crap out of many surfaces. I am sure that we can agree that type of attitude is unacceptable. The use of soft washing is capable of achieving the desired outcome with no damage. That is the only option as a responsible roof cleaner.

The question is why am on on your site, the experiences some of you have encountered in the inspection process and damage caused by cleaning a roof the irresponsible way. I have a local competitor who has been educating people that pressure washing roofs does no damage etc. and there are many out there just like him.

What I hope is that based on your members experiences, passing on the knowledge in a constructive way to educate what is an acceptable maintenance practice for roof cleaning and the damages as a result of pressure washing roofs can do.

Take Care,

Kim R

[KimR]

Hey Gary Wyer, Roof Cleaning Institute Of America Master Certified Roof Cleaning Instructor. I just read some stuff you wrote:

"Not taking care of roof algae can lead to increased home and cooling costs and will deteriorate the shingles".

Really - got any proof?

"It will begin to feed on the shingles and will spread over time eventually taking over the entire roof".

"...it is an airborne algae technically called Gloeocapsa Magma. It gets on the roof, survives by feeding on nutrients in the shingles, and is spread down the roof by rain creating the black streaks".

Bullshit. Gloeocapsa Magma is NOT an algea, it's a cyanobacteria. It does NOT feed on the shingles or nutrients in the shingles. See my post, #8 above.

Bill

Here is some scientific research that I have found you might find useful.

Lichen FAQ

Biodeterioration

University of California Berkley Lab Study

These are a few and some are quite long to read, but some food for thought.I do have a few more, if you are interested. This has never been a very well researched topic and has many opinions. We have our own personal opinion on damage and seen it first hand as that is what we do in MI., roof replacement. It is (streaking) commonplace in Fl. but it has really starting to run rampant now in Mi. been roofing for 28 yrs and never have had this issue. We see it pretty much on homes built about 12-17 years ago. Some newer.

Take Care

Kim R

[Tim Maxwell]

I would like to personally thank the pressure washing roof cleaner guy for officially getting Mike into the holiday spirit.

Merry Christmas ya filthy terrorist.....[:-party]

[hausdok]

Learned everything I know from this guy.

ONE TEAM - ONE FIGHT!!!

Mike[utube]" type="application/x-shockwave-flash" wmode="transparent" width="425" height="344">

[Marc]

I've been experimenting over the past year with oxygen bleach and roof cleaning. Done experimented so much that there too little algae residue left on my roof to continue, so my good neighbor allowed me to indulge myself on his. His is one of the very worse ones in our subdivision. I capture and monitor all granule loss. Factors are bleach concentration, water temperature, elapse time before washing it off, ambiant temps and others. So far, I've found that soft bristle brushes aren't forceful enough to remove it all. Pressure washers, even the little one that I have, remove too much granule. Some of the granule will come off regardless of how you do it, comes off with every rainfall anyway. What I'm looking to do at this point is adapt the throttle on a gas powered pressure washer so that I have control of the pressure. This may allow me to strike a balance between algae removal and granule loss.

I've been working on this idea and a couple other things to augment my income.

Shucking pressure washing machines altogether doesn't make sense. It's the amount of pressure and the condition of the particular roof that you're working on that matters, among other things.

Marc

[hausdok]

Shucking pressure washing machines altogether doesn't make sense. It's the amount of pressure and the condition of the particular roof that you're working on that matters, among other things.

Marc

I agree, that's why I said I only hate 99.9999999% of roof cleaners. There's a couple of companies around here that use HVLP techniques to clean roofs and they do an excellent job with very little granule loss and without damaging the covers. Whenever a client wants to know how to clean the roof, I tell them not to bother and recommend that he or she call one of those guys.

ONE TEAM - ONE FIGHT!!!

Mike

[hausdok]

Mike,

I sent an email to you originally to discuss the roof cleaning that is discussed here. Kim R

You did? When was that? Did I answer? Sorry if I'm unable to remember; I'm not real good at keeping track of emails that I answer.

ONE TEAM - ONE FIGHT!!!

Mike

[KimR]

Mike,

I sent an email to you originally to discuss the roof cleaning that is discussed here. Kim R

You did? When was that? Did I answer? Sorry if I'm unable to remember; I'm not real good at keeping track of emails that I answer.

ONE TEAM - ONE FIGHT!!!

Mike

Mike

I am not sure it made it to you, But I want to really let you know is, I and many others are totally against roof cleaning and pressure washing!

In retiring from roof replacement, we are going into roof cleaning and maintenance. RCIA is a forum that is promotes non pressure cleaning methods and the forum owner has been doing it this way for over 20 yrs. We currently have about 1400 members all over the US and some in other country's. RCIA is diligently working to train and educate many roof cleaners the non-pressure way to clean a roof. In essence the one percent you are talking about is really growing. I welcome for you or any other inspectors to give us a look.I think you might be surprised how really involved roof cleaning has become.

The link is

RCIA

RCIA could really use some of the experience's you guys have in educating consumers on the damages caused by pressure washing roofs. In the end your forum and ours seek to permanently ban all pressurewashers on roofs. Thank you for your time Mike,

Sincerely,

Kim R

[KimR]

I've been experimenting over the past year with oxygen bleach and roof cleaning. Done experimented so much that there too little algae residue left on my roof to continue, so my good neighbor allowed me to indulge myself on his. His is one of the very worse ones in our subdivision. I capture and monitor all granule loss. Factors are bleach concentration, water temperature, elapse time before washing it off, ambiant temps and others. So far, I've found that soft bristle brushes aren't forceful enough to remove it all. Pressure washers, even the little one that I have, remove too much granule. Some of the granule will come off regardless of how you do it, comes off with every rainfall anyway. What I'm looking to do at this point is adapt the throttle on a gas powered pressure washer so that I have control of the pressure. This may allow me to strike a balance between algae removal and granule loss.

I've been working on this idea and a couple other things to augment my income.

Shucking pressure washing machines altogether doesn't make sense. It's the amount of pressure and the condition of the particular roof that you're working on that matters, among other things.

Shuck the machine get a roof pump with a tank and some chems. There are many ways to apply chemicals to the roof, high tech and low tech cheaper ways , but they ALL use absolutely no pressure. If this is an avenue you choose please read through the threads as there are other things you need to know before you have at it.

Hope this helps,

Kim R

Check this out as a starter package:

Roof cleaning set-up

[Jim Katen]

. . . There are many ways to apply chemicals to the roof, high tech and low tech cheaper ways , but they ALL use absolutely no pressure. . . .

How can you move a liquid from one place to another using "absolutely no pressure" ???

[JeremyDP]

. . . There are many ways to apply chemicals to the roof, high tech and low tech cheaper ways , but they ALL use absolutely no pressure. . . .

How can you move a liquid from one place to another using "absolutely no pressure" ???

I'm guessing, er hoping, that Kim means "absolutely no pressure ".

[hausdok]

Mike,

I sent an email to you originally to discuss the roof cleaning that is discussed here. Kim R

You did? When was that? Did I answer? Sorry if I'm unable to remember; I'm not real good at keeping track of emails that I answer.

ONE TEAM - ONE FIGHT!!!

Mike

Mike

I am not sure it made it to you, But I want to really let you know is, I and many others are totally against roof cleaning and pressure washing!

In retiring from roof replacement, we are going into roof cleaning and maintenance. RCIA is a forum that is promotes non pressure cleaning methods and the forum owner has been doing it this way for over 20 yrs. We currently have about 1400 members all over the US and some in other country's. RCIA is diligently working to train and educate many roof cleaners the non-pressure way to clean a roof. In essence the one percent you are talking about is really growing. I welcome for you or any other inspectors to give us a look.I think you might be surprised how really involved roof cleaning has become.

The link is

RCIA

RCIA could really use some of the experience's you guys have in educating consumers on the damages caused by pressure washing roofs. In the end your forum and ours seek to permanently ban all pressurewashers on roofs. Thank you for your time Mike,

Sincerely,

Kim R

Hey,

Any organization that will work to get the pressure washers out of the hands of the legion of ijjits I see running around here blasting away at roofs with 1000#+ pressure is OK by me.

ONE TEAM - ONE FIGHT!!!

Mike

[KimR]

. . . There are many ways to apply chemicals to the roof, high tech and low tech cheaper ways , but they ALL use absolutely no pressure. . . .

How can you move a liquid from one place to another using "absolutely no pressure" ???

I'm guessing, er hoping, that Kim means "absolutely no pressure ".

No, no pressure washer ever! we use a pump delivery system that moves the water(chems ) equivalent to a garden hose.It is called a soft wash.

Here are some before & afters.

Click to Enlarge

36.54 KB

Click to Enlarge

45.12 KB

And here is some homeowners idea of roof cleaning[:-censore

Click to Enlarge

106.1 KB

Hope this help to understand the cleaning process and the big difference between the two.

Take Care,

Kim

[hausdok]

And here is some homeowners idea of roof cleaning

Click to Enlarge

106.1 KB

Hope this help to understand the cleaning process and the big difference between the two.

Take Care,

Kim

Homeowner?

Hell, around here, that's how a most of these "professional" roof cleaners leave the roofs.

You should see what they do to expensive shake roofs.

ONE TEAM - ONE FIGHT!!!

Mike

[Brandon Whitmore]

Hi Kim,

On those roof cleaning pictures, is the "algae" removed and killed off, or just bleached?

In your area, how long does it take for algae to form on a new roof?

After a good roof cleaning, how long does it take to come back?

Do you consider the cleaning procedure to be cosmetic, or do you figure removal of the algae will prolong the life of the roof covering?

Thanks.

[KimR]

And here is some homeowners idea of roof cleaning

Click to Enlarge

106.1 KB

Hope this help to understand the cleaning process and the big difference between the two.

Take Care,

Kim

Homeowner?

Hell, around here, that's how a most of these "professional" roof cleaners leave the roofs.

You should see what they do to expensive shake roofs.

ONE TEAM - ONE FIGHT!!!

Mike

Mike

Those guys that do that ahh, ya have no place on a roof, EVER!

Lazy ignorant hacks! That needs to change, the people in your area and other areas need to know that do not have to settle for less and there is a better choice. One that does not damage a good roofing system.

As far as cedar shakes that is a whole nother ball game and are way more vulnerable to improper cleaning methods. To clean Cedar roofs or any other wood surface is an art, not just anyone should do this.

Mike if you would like I can see if there are a few more guys that are in your area?

Take care, Kim

[KimR]

Wow Mike ,

I feel for you, I just googled roof cleaners in Kenmore Washington, all I can say is WOW!, there are guys ruining roofs and totally getting away with it.

That has got to change, let me work on this at RCIA and see if we can drum up a few guys to get some alternatives for Washington or who ever sles might be dealing with this in there area.

This will be the topic for the week over on our end.

Take Care,

Kim R

[KimR]

Originally posted by Brandon Whitmore

Hi Kim,

On those roof cleaning pictures, is the "algae" removed and killed off, or just bleached? We use Sodium Hypochlorite not bleach, bleach is a very weakened form from Chlorine.

In your area, how long does it take for algae to form on a new roof?

Florida is more susceptible than the northern areas, but in reality anywhere the weather conditions such as high humidity and a long rainy season are prime for recurrence.

We have a guy that has soft wash cleaned in Fl over 50,000 roofs, never causing any roof damage. He has designed through out the years a product that carry's a 5 yr warranty. In essence if they can offer 5 yrs in Fl, it would be safe to say the cleaning process in areas like Mi. it could fall into a possible 7-10 yr warranty. ( We have had a roofing business in Mi. for 27 yrs or so, and are opening up a roof cleaning business in Fl, and possibly looking at Mi. as well)

After a good roof cleaning, how long does it take to come back?

There are a variety of factors for a re-infestation, after a "good" roof cleaning and the right way to clean are two factors. The right way is to kill the algae( general term here, ok?) or other growths is probably a big factor.

The other cause is your neighborhood, if it is really bad it probably will make its way back to you. I could get into the whole science thing that this stuff has been around since time and can survive the trip in space, but you get my point. All in all it is very hardy, and using the wrong cleaning method can bring this back fairly quick, a year or two?

Do you consider the cleaning procedure to be cosmetic, or do you figure removal of the algae will prolong the life of the roof covering?

The removal of the algae, is not the way I would word this, I would say that in killing it, it will follow the normal process as with anything that is dead, it will decompose etc.

As far as the cleaning being cosmetic, here is a link to read what has been talked about from a roof cleaners point of view:

RCIA

My personal thought as a roof replacement company working in Mi. we are starting to see the shingle granules being compromised, a loss of some granules might be acceptable, but the weathering in addition to significant loss of granules in my opinion add up to premature failure. We recently replaced a 10 yr old roof and I posted the images on the web site I posted here. You can decide if you view those images and format your own opinion.

Aesthetics are one part of the equation, as in FL many HOA's enforce this cleaning, in the north as in Mi. not so much, but There are many that have very expensive homes and value the curb appeal of their 400k home. So that would motivate them.

Increased heating costs are another issue as well, and if anyone has read and understood that what is growing on the roof attracts the Sun's rays to keep it alive, this is a part of that equation.

Here is a link to some elementary science from 3M and Discovery Science, while elementary it will give a basic understanding. Kind cool stuff.

3M Discovery Science

All in all it is way more complex than I would have ever anticipated, but interesting.

Hope this helps you understand this a little more.

Take Care,

Kim

[Jim Katen]

Hi Kim,

On those roof cleaning pictures, is the "algae" removed and killed off, or just bleached? We use Sodium Hypochlorite not bleach, bleach is a very weakened form from Chlorine.

Sodium hypochlorite *is* bleach.

And you didn't answer the question.

In your area, how long does it take for algae to form on a new roof?

Florida is more susceptible than the northern areas, but in reality anywhere the weather conditions such as high humidity and a long rainy season are prime for recurrence.

We have a guy that has soft wash cleaned in Fl over 50,000 roofs, never causing any roof damage. He has designed through out the years a product that carry's a 5 yr warranty. In essence if they can offer 5 yrs in Fl, it would be safe to say the cleaning process in areas like Mi. it could fall into a possible 7-10 yr warranty. ( We have had a roofing business in Mi. for 27 yrs or so, and are opening up a roof cleaning business in Fl, and possibly looking at Mi. as well)

You didn't answer the question.

After a good roof cleaning, how long does it take to come back?

There are a variety of factors for a re-infestation, after a "good" roof cleaning and the right way to clean are two factors. The right way is to kill the algae( general term here, ok?) or other growths is probably a big factor.

The other cause is your neighborhood, if it is really bad it probably will make its way back to you. I could get into the whole science thing that this stuff has been around since time and can survive the trip in space, but you get my point. All in all it is very hardy, and using the wrong cleaning method can bring this back fairly quick, a year or two?

You didn't answer the question.

Do you consider the cleaning procedure to be cosmetic, or do you figure removal of the algae will prolong the life of the roof covering?

The removal of the algae, is not the way I would word this, I would say that in killing it, it will follow the normal process as with anything that is dead, it will decompose etc.

As far as the cleaning being cosmetic, here is a link to read what has been talked about from a roof cleaners point of view:

RCIA

That link has nothing to do with the question.

My personal thought as a roof replacement company working in Mi. we are starting to see the shingle granules being compromised, a loss of some granules might be acceptable, but the weathering in addition to significant loss of granules in my opinion add up to premature failure. We recently replaced a 10 yr old roof and I posted the images on the web site I posted here. You can decide if you view those images and format your own opinion.

Aesthetics are one part of the equation, as in FL many HOA's enforce this cleaning, in the north as in Mi. not so much, but There are many that have very expensive homes and value the curb appeal of their 400k home. So that would motivate them.

Increased heating costs are another issue as well, and if anyone has read and understood that what is growing on the roof attracts the Sun's rays to keep it alive, this is a part of that equation.

Here is a link to some elementary science from 3M and Discovery Science, while elementary it will give a basic understanding. Kind cool stuff.

Lots of words, but nothing addressing the simple question that was asked.

All in all it is way more complex than I would have ever anticipated, but interesting.

Hope this helps you understand this a little more.

Take Care,

Kim

Aside from your laudable aversion to pressure washing, I've heard nothing from you that indicates you have any specialized or complete understanding of roofing at all. You write lots of words, but most of them make no sense. And, so far, you haven't contributed anything meaningful to this thread that hadn't already been amply expressed by others. As far as I can see you're about a half step above the link droppers that occasionally pepper this site.

- Jim Katen, Oregon

[Tom Raymond]

I have no problem believing this guy is a roofer, most of them are illiterate. It's clear from his posts that he's only marginally more skilled.

[JeremyDP]

Roof shingles and this algea seem to be like the chicken and the egg.

High moisture is bad for shingles but the algea loves it. So are the shingles deteriorating due to the moisture or the algae? Has no scientist researched this?