I had new roofing installed (GAF 50 year asphalt shingles) about 5
years ago. I've noticed that over the past year its started to
develop growing moss and algae on certain sections which are located
under tall oak trees. The old roof, under the same trees for 30 years
had NONE of this growth. I've also noticed that on one side of my
house, the same end of the house with the roof moss, has algae growing
relatively significantly on my white alum siding. Again, only the
past year or so.

This side is south facing and there are no side trees blocking
horizontal sun exposure.

So, my questions a

What might be causing this condition starting only this past year?

What damage is being caused by the moss on the shingles?

What could I do to eliminate and prevent future growth?

Any possible recourse with the shingle manufacturer?

Thanks for any/all advice provided.

B

What could I do to eliminate and prevent future growth?

You can't beat this product.

http://www.sprayandforget.com/

wrote in message
...
I had new roofing installed (GAF 50 year asphalt shingles) about 5
years ago. I've noticed that over the past year its started to
develop growing moss and algae on certain sections which are located
under tall oak trees. The old roof, under the same trees for 30 years
had NONE of this growth. I've also noticed that on one side of my
house, the same end of the house with the roof moss, has algae growing
relatively significantly on my white alum siding. Again, only the
past year or so.

This side is south facing and there are no side trees blocking
horizontal sun exposure.

So, my questions a

What might be causing this condition starting only this past year?

What damage is being caused by the moss on the shingles?

What could I do to eliminate and prevent future growth?

Any possible recourse with the shingle manufacturer?

Thanks for any/all advice provided.

B


Very first result from Bing
search....http://www.askthebuilder.com/539-Rem...om-Roofs.shtml

Brush it off with a stiff bristle brush and add copper strips under the cap
with an inch or 2 of copper exposed....

wrote:
What could I do to eliminate and prevent future growth?

You can't beat this product.

http://www.sprayandforget.com/

I don't trust anything that says it's "eco-friendly".

Jon

"benick" wrote in
:


wrote in message
...
I had new roofing installed (GAF 50 year asphalt shingles) about 5
years ago. I've noticed that over the past year its started to
develop growing moss and algae on certain sections which are located
under tall oak trees. The old roof, under the same trees for 30
years had NONE of this growth. I've also noticed that on one side of
my house, the same end of the house with the roof moss, has algae
growing relatively significantly on my white alum siding. Again,
only the past year or so.

This side is south facing and there are no side trees blocking
horizontal sun exposure.

So, my questions a

What might be causing this condition starting only this past year?

What damage is being caused by the moss on the shingles?

What could I do to eliminate and prevent future growth?

Any possible recourse with the shingle manufacturer?

Thanks for any/all advice provided.

B


Very first result from Bing
search....http://www.askthebuilder.com/539-Rem...and-Algae-From
-Roofs.shtml

Brush it off with a stiff bristle brush and add copper strips under
the cap with an inch or 2 of copper exposed....



Zinc strips are often used. Lot less expensive. Have no knowledge of
comparison of effectiveness.

Very first result from Bing
search....http://www.askthebuilder.com/539-Rem...om-Roofs.shtml

Brush it off with a stiff bristle brush and add copper strips under the cap
with an inch or 2 of copper exposed....

If you agree to put up with the removal of the particles that make
up a shingle and thus shorten its life, then this scrubbing motion
will certainly remove the moss and algae and a portion of the
shingle..


The smart way to remove algae is to not use any scrubbing motion
at all. Just apply a long lasting chemical that will eventually kill
the growth. Then with periodic applications of once every two
years this same chemical will maintain a algae free roof.

http://www.sprayandforget.com/

On Thu, 26 Nov 2009 18:38:50 -0800, "Jon Danniken"
wrote:

wrote:
What could I do to eliminate and prevent future growth?

You can't beat this product.

http://www.sprayandforget.com/

I don't trust anything that says it's "eco-friendly".

Jon

I don't care if it's eco friendly or not. It works. I had black algae
stains all over my white shingled roof. They are gone. Not plants
or animals were harmed in the process.

What could I do to eliminate and prevent future growth?

ZINC strips..Google 'zinc roof strips': buy and put them up per
instructions

On Thu, 26 Nov 2009 23:36:13 -0500, wrote:

-snip-

you need to make up your mind-

I don't care if it's eco friendly or not. It works. I had black algae
stains all over my white shingled roof. They are gone. Not plants
or animals were harmed in the process.

We know that statement is false. The question now, is 'what else was
killed besides the lowly algae.

Jim

Eco-friendly equals "doesn't work".
New and improved equals "we left out two ingredients and
raised the price".

The list goes on.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"Jon Danniken" wrote in
message ...
wrote:
What could I do to eliminate and prevent future growth?

You can't beat this product.

http://www.sprayandforget.com/

I don't trust anything that says it's "eco-friendly".

Jon

On Nov 26, 6:56*pm, wrote:
I had new roofing installed (GAF 50 year asphalt shingles) about 5
years ago. *I've noticed that over the past year its *started to
develop growing moss and algae on certain sections which are located
under tall oak trees. *The old roof, under the same trees for 30 years
had NONE of this growth. *I've also noticed that on one side of my
house, the same end of the house with the roof moss, has algae growing
relatively significantly on my white alum siding. *Again, only the
past year or so.

This side is south facing and there are no side trees blocking
horizontal sun exposure.

So, my questions a

What might be causing this condition starting only this past year?

What damage is being caused by the moss on the shingles?

What could I do to eliminate and prevent future growth?

Any possible recourse with the shingle manufacturer?

Thanks for any/all advice provided.

B

Is new roof the same color and texture, I could understand a more
agressive texture or style holding tree debris instead of alowing it
to wash off since oaks drop sticky sap in early summer, a different
color would not heat up the same as the old roof from the sun
affecting what lives. I would not scrub the roof. Zinc strips at the
peak might help. Contact the roof co, bleach and other "moss"
treatments will kill mold and moss but will it ruin the roofs life
expectancy? Your store bought moss treatments probably have Sodium
Hypochlorate as the main ingrediant, thats just Laundry bleach for 10x
the price. Contact GAF.

benick wrote:
wrote in message
...
I had new roofing installed (GAF 50 year asphalt shingles) about 5
years ago. I've noticed that over the past year its started to
develop growing moss and algae on certain sections which are located
under tall oak trees. The old roof, under the same trees for 30
years had NONE of this growth. I've also noticed that on one side
of my house, the same end of the house with the roof moss, has
algae growing relatively significantly on my white alum siding. Again,
only the past year or so.

This side is south facing and there are no side trees blocking
horizontal sun exposure.

So, my questions a

What might be causing this condition starting only this past year?

What damage is being caused by the moss on the shingles?

What could I do to eliminate and prevent future growth?

Any possible recourse with the shingle manufacturer?

Thanks for any/all advice provided.

B


Very first result from Bing
search....http://www.askthebuilder.com/539-Rem...om-Roofs.shtml

Brush it off with a stiff bristle brush and add copper strips under
the cap with an inch or 2 of copper exposed....

I don't know if copper will kill the moss and algae but it will cause green
stains on the roof, so there may be no change in appearance. Zinc kills moss
and algae and oxidizes as white and may not cause any visible stains on the
roof while eliminating the green.

Stormin Mormon wrote:
Eco-friendly equals "doesn't work".
New and improved equals "we left out two ingredients and
raised the price".

The list goes on.

The nonsense goes on, you mean.

Statements like this just display an inability or unwillingness to think.





"Jon Danniken" wrote in
message ...
wrote:
What could I do to eliminate and prevent future growth?

You can't beat this product.

http://www.sprayandforget.com/

I don't trust anything that says it's "eco-friendly".

Jon

Rudy wrote:
What could I do to eliminate and prevent future growth?

ZINC strips..Google 'zinc roof strips': buy and put them up per
instructions

Then hope the do anything. They didn't stop the moss on my neighbor's roof.

ransley wrote:
On Nov 26, 6:56 pm, wrote:
I had new roofing installed (GAF 50 year asphalt shingles) about 5
years ago. I've noticed that over the past year its started to
develop growing moss and algae on certain sections which are located
under tall oak trees. The old roof, under the same trees for 30 years
had NONE of this growth. I've also noticed that on one side of my
house, the same end of the house with the roof moss, has algae
growing relatively significantly on my white alum siding. Again,
only the past year or so.

This side is south facing and there are no side trees blocking
horizontal sun exposure.

So, my questions a

What might be causing this condition starting only this past year?

What damage is being caused by the moss on the shingles?

What could I do to eliminate and prevent future growth?

Any possible recourse with the shingle manufacturer?

Thanks for any/all advice provided.

B

Is new roof the same color and texture, I could understand a more
agressive texture or style holding tree debris instead of alowing it
to wash off since oaks drop sticky sap in early summer, a different
color would not heat up the same as the old roof from the sun
affecting what lives. I would not scrub the roof. Zinc strips at the
peak might help. Contact the roof co, bleach and other "moss"
treatments will kill mold and moss but will it ruin the roofs life
expectancy? Your store bought moss treatments probably have Sodium
Hypochlorate as the main ingrediant, thats just Laundry bleach for 10x
the price. Contact GAF.

Some roofing material has things added to stop moss growth. Other doesn't.

Jon Danniken wrote:
wrote:
What could I do to eliminate and prevent future growth?
You can't beat this product.

http://www.sprayandforget.com/

I don't trust anything that says it's "eco-friendly".

Jon



What if it says "Made from baby seals"? Whenever I'm in a
grocery store and the checker asks me if I want paper or
plastic, I always tell them that I want whatever is worst
for the environment. They never get it right. *snicker*

TDD

Stormin Mormon wrote:
Eco-friendly equals "doesn't work".
New and improved equals "we left out two ingredients and
raised the price".

The list goes on.


Don't forget the "government agency X approved" label.

TDD

Red Green wrote:
"benick" wrote in
:

wrote in message
...
I had new roofing installed (GAF 50 year asphalt shingles) about 5
years ago. I've noticed that over the past year its started to
develop growing moss and algae on certain sections which are located
under tall oak trees. The old roof, under the same trees for 30
years had NONE of this growth. I've also noticed that on one side of
my house, the same end of the house with the roof moss, has algae
growing relatively significantly on my white alum siding. Again,
only the past year or so.

This side is south facing and there are no side trees blocking
horizontal sun exposure.

So, my questions a

What might be causing this condition starting only this past year?

What damage is being caused by the moss on the shingles?

What could I do to eliminate and prevent future growth?

Any possible recourse with the shingle manufacturer?

Thanks for any/all advice provided.

B

Very first result from Bing
search....http://www.askthebuilder.com/539-Rem...and-Algae-From
-Roofs.shtml

Brush it off with a stiff bristle brush and add copper strips under
the cap with an inch or 2 of copper exposed....



Zinc strips are often used. Lot less expensive. Have no knowledge of
comparison of effectiveness.

I thought copper worked too?

TDD

Meat Plow wrote:
On Fri, 27 Nov 2009 10:29:11 -0600, The Daring Dufas
wrote:

Red Green wrote:
"benick" wrote in
:

wrote in message
...
I had new roofing installed (GAF 50 year asphalt shingles) about 5
years ago. I've noticed that over the past year its started to
develop growing moss and algae on certain sections which are located
under tall oak trees. The old roof, under the same trees for 30
years had NONE of this growth. I've also noticed that on one side of
my house, the same end of the house with the roof moss, has algae
growing relatively significantly on my white alum siding. Again,
only the past year or so.

This side is south facing and there are no side trees blocking
horizontal sun exposure.

So, my questions a

What might be causing this condition starting only this past year?

What damage is being caused by the moss on the shingles?

What could I do to eliminate and prevent future growth?

Any possible recourse with the shingle manufacturer?

Thanks for any/all advice provided.

B

Very first result from Bing
search....http://www.askthebuilder.com/539-Rem...and-Algae-From
-Roofs.shtml

Brush it off with a stiff bristle brush and add copper strips under
the cap with an inch or 2 of copper exposed....


Zinc strips are often used. Lot less expensive. Have no knowledge of
comparison of effectiveness.
I thought copper worked too?

TDD

I use strips made from the pelts of baby seals.

Which part of them do you eat first?

TDD

tnom wrote:
wrote:

http://www.sprayandforget.com/

I don't care if it's eco friendly or not. It works. I had black algae
stains all over my white shingled roof. They are gone. Not plants or
animals were harmed in the process.

Do you have a bottle of Spray and Forget handy? If so, would you please
post the listed active ingredients from the label?

--
Tony Sivori
Due to spam, I'm filtering all Google Groups posters.

bobm3 wrote:

I had new roofing installed (GAF 50 year asphalt shingles) about 5 years
ago. I've noticed that over the past year its started to develop
growing moss and algae on certain sections which are located under tall
oak trees.
The old roof, under the same trees for 30 years had NONE of this
growth.
I've also noticed that on one side of my house, the same end of the
house with the roof moss, has algae growing relatively significantly on
my white alum siding. Again, only the past year or so.

This side is south facing and there are no side trees blocking
horizontal sun exposure.

So, my questions a

What might be causing this condition starting only this past year?

Considering it recently started on the siding along with the relatively
new shingles, I'd say the new shingles has little or nothing to do with
the problem.

As your trees grow, the shade becomes denser, which promotes moss, fungus
and algae. Temperature, moisture and humidity are also factors. Perhaps
this years weather promoted growth more than average.

What damage is being caused by the moss on the shingles?

Over time, plenty. You don't want to let this go unsolved.

What could I do to eliminate and prevent future growth?

There are a variety of chemical treatments, plus the metal strip method.

Trim the trees back so the roof gets more sun.

Any possible recourse with the shingle manufacturer?

Maybe. Did they give you an ironclad guarantee against all moss, fungus,
algae and mildew growth? If not, I suspect that you're on your own.

Thanks for any/all advice provided.

I had the same problem on my roof this year, in a shady spot that sounds
similar to yours. I had both moss and fungus well established on the roof.

I considered a bleach solution, but I was worried about the affect it
might have on the asphalt fiberglass shingles on my roof.

I checked all the products at Lowes, and all I found was siding and deck
wash products did not mention use on roofs.

So I took a chance, and sprayed a weed killer on it one afternoon when
heavy rain was forecast for that night. It looks to have killed about 90%
of it. But since I don't know what that might have done to shorten the
life of the shingles, I don't recommend doing what I did.


--
Tony Sivori
Due to spam, I'm filtering all Google Groups posters.

Meat Plow wrote:

The Daring Dufas wrote:

I thought copper worked too?

I use strips made from the pelts of baby seals.

You're not nice!

--
Tony Sivori
Due to spam, I'm filtering all Google Groups posters.

Bob F wrote:

Stormin Mormon wrote:
Eco-friendly equals "doesn't work".
New and improved equals "we left out two ingredients and raised the
price".

The list goes on.

The nonsense goes on, you mean.

Statements like this just display an inability or unwillingness to
think.

http://tinyurl.com/yd4pn4m

--
Tony Sivori
Due to spam, I'm filtering all Google Groups posters.

The Daring Dufas wrote in
:

Red Green wrote:
"benick" wrote in
:

wrote in message
...
I had new roofing installed (GAF 50 year asphalt shingles) about 5
years ago. I've noticed that over the past year its started to
develop growing moss and algae on certain sections which are
located under tall oak trees. The old roof, under the same trees
for 30 years had NONE of this growth. I've also noticed that on
one side of my house, the same end of the house with the roof moss,
has algae growing relatively significantly on my white alum siding.
Again, only the past year or so.

This side is south facing and there are no side trees blocking
horizontal sun exposure.

So, my questions a

What might be causing this condition starting only this past year?

What damage is being caused by the moss on the shingles?

What could I do to eliminate and prevent future growth?

Any possible recourse with the shingle manufacturer?

Thanks for any/all advice provided.

B

Very first result from Bing
search....http://www.askthebuilder.com/539-Rem...s-and-Algae-Fr
om -Roofs.shtml

Brush it off with a stiff bristle brush and add copper strips under
the cap with an inch or 2 of copper exposed....



Zinc strips are often used. Lot less expensive. Have no knowledge of
comparison of effectiveness.

I thought copper worked too?

TDD


Yep, that's my understanding as well. I believe they use zinc and copper
in shingles during manufacture. These are usually called AR (algae
resistant) Shingles. Note "Resistant" which is totally subjective and
arguable. I do not know if there is a independent spec to be classified
as AR.

"Jon Danniken" wrote in message
...
wrote:
What could I do to eliminate and prevent future growth?

You can't beat this product.

http://www.sprayandforget.com/

I don't trust anything that says it's "eco-friendly".

Jon


I'm aware this maybe just a joke but:

Some Eco Friendly products work better. The first one that comes to mind is
the orange based auto part cleaner. I'm not sure my Prius is considered "EF"
but they are really great cars that get fantastic mileage and used to be
affordable.

I'm sure the list goes on and on.

Jim

On Fri, 27 Nov 2009 12:45:00 -0500, Tony Sivori
wrote:

tnom wrote:
wrote:

http://www.sprayandforget.com/

I don't care if it's eco friendly or not. It works. I had black algae
stains all over my white shingled roof. They are gone. Not plants or
animals were harmed in the process.

Do you have a bottle of Spray and Forget handy? If so, would you please
post the listed active ingredients from the label?

Benzylkonium Chloride

From Wiki: http://en.wikipedia.org/wiki/Benzalkonium_chloride

It is used in pharmaceuticals such as leave-on skin antiseptics,
hygienic towelettes, and wet wipes, Lysol and ethanol-free solutions
are often used in preparations used for skin disinfection prior to use
of syringes.

So I took a chance, and sprayed a weed killer on it one afternoon when
heavy rain was forecast for that night. It looks to have killed about 90%
of it. But since I don't know what that might have done to shorten the
life of the shingles, I don't recommend doing what I did.

I thought you were concerned with Eco-Friendly products? Or is it just
a concern when others use them?

wrote in :

On Fri, 27 Nov 2009 12:45:00 -0500, Tony Sivori
wrote:

tnom wrote:
wrote:

http://www.sprayandforget.com/

I don't care if it's eco friendly or not. It works. I had black algae
stains all over my white shingled roof. They are gone. Not plants or
animals were harmed in the process.

Do you have a bottle of Spray and Forget handy? If so, would you please
post the listed active ingredients from the label?

Benzylkonium Chloride

From Wiki: http://en.wikipedia.org/wiki/Benzalkonium_chloride

It is used in pharmaceuticals such as leave-on skin antiseptics,
hygienic towelettes, and wet wipes, Lysol and ethanol-free solutions
are often used in preparations used for skin disinfection prior to use
of syringes.


Nice suff...Wonder if Rover will be rigid yet when Mr Fixit comes off the
roof.


[from the link]

Benzalkonium chloride, also known as alkyldimethylbenzylammonium chloride
and ADBAC,
.....
ADBAC is highly toxic to fish (LC50 = 280 ?g ai/L), very highly toxic to
aquatic invertebrates (LC50 = 5.9 ?g ai/L), moderately toxic to birds
(LD50 = 136 mg/kg-bw), and slightly toxic to mammals (LD50 = 430 mg/kg-
bw).[4] Benzalkonium chloride solutions of 10% or more are toxic to
humans, causing irritation to the skin and mucosa, and death if taken
internally.[5]

Wow! Thanks everyone for quite of bit of education. I am going to try the
product mentioned first and next spring try the zinc plates for an ongoing
effect.

Thanks again all - this was great!

Bob

On Fri, 27 Nov 2009 22:26:55 -0500, wrote:


So I took a chance, and sprayed a weed killer on it one afternoon when
heavy rain was forecast for that night. It looks to have killed about 90%
of it. But since I don't know what that might have done to shorten the
life of the shingles, I don't recommend doing what I did.

I thought you were concerned with Eco-Friendly products? Or is it just
a concern when others use them?

If by "weedkiller" he meant Roundup, then it was quite eco-friendly.
The stuff is approved for use on food crops.

Do you have a bottle of Spray and Forget handy? If so, would you please
post the listed active ingredients from the label?

Benzylkonium Chloride

From Wiki: http://en.wikipedia.org/wiki/Benzalkonium_chloride

It is used in pharmaceuticals such as leave-on skin antiseptics,
hygienic towelettes, and wet wipes, Lysol and ethanol-free solutions
are often used in preparations used for skin disinfection prior to use
of syringes.


Nice suff...Wonder if Rover will be rigid yet when Mr Fixit comes off the
roof.


[from the link]

Benzalkonium chloride, also known as alkyldimethylbenzylammonium chloride
and ADBAC,
....
ADBAC is highly toxic to fish (LC50 = 280 ?g ai/L), very highly toxic to
aquatic invertebrates (LC50 = 5.9 ?g ai/L), moderately toxic to birds
(LD50 = 136 mg/kg-bw), and slightly toxic to mammals (LD50 = 430 mg/kg-
bw).[4] Benzalkonium chloride solutions of 10% or more are toxic to
humans, causing irritation to the skin and mucosa, and death if taken
internally.[5]

10% ? The concentration of Benzalkonium chloride in the use of
this product is not even close to 10%

Internally? Do you take gasoline, bleach, or bullets internally?
If so then I would also be concerned with Benzalkonium chloride.

Jeff The Drunk, BITCH wrote:
On Fri, 27 Nov 2009 10:54:03 -0600, The Daring Dufas
wrote:

Meat Plow wrote:
On Fri, 27 Nov 2009 10:29:11 -0600, The Daring Dufas
wrote:

Red Green wrote:
"benick" wrote in
:

wrote in message
...
I had new roofing installed (GAF 50 year asphalt shingles) about 5
years ago. I've noticed that over the past year its started to
develop growing moss and algae on certain sections which are located
under tall oak trees. The old roof, under the same trees for 30
years had NONE of this growth. I've also noticed that on one side of
my house, the same end of the house with the roof moss, has algae
growing relatively significantly on my white alum siding. Again,
only the past year or so.

This side is south facing and there are no side trees blocking
horizontal sun exposure.

So, my questions a

What might be causing this condition starting only this past year?

What damage is being caused by the moss on the shingles?

What could I do to eliminate and prevent future growth?

Any possible recourse with the shingle manufacturer?

Thanks for any/all advice provided.

B

Very first result from Bing
search....http://www.askthebuilder.com/539-Rem...and-Algae-From
-Roofs.shtml

Brush it off with a stiff bristle brush and add copper strips under
the cap with an inch or 2 of copper exposed....


Zinc strips are often used. Lot less expensive. Have no knowledge of
comparison of effectiveness.
I thought copper worked too?

TDD
I use strips made from the pelts of baby seals.
Which part of them do you eat first?

TDD

Eat baby seals? That's not nice!

It's a sin to let food go to waste. If you kill an animal,
(crack heads are the exception) you must eat it or give it
to the less fortunate so they may not starve.

TDD

tnom wrote:
[attributes restored]
Tony Sivori wrote:
So I took a chance, and sprayed a weed killer on it one afternoon when
heavy rain was forecast for that night. It looks to have killed about
90% of it. But since I don't know what that might have done to shorten
the life of the shingles, I don't recommend doing what I did.

I thought you were concerned with Eco-Friendly products? Or is it just a
concern when others use them?

I don't know where you got that idea, given that I've never posted my
position on that topic.

So many companies greenwash their product that the "green" or
"Environmentally friendly" tags have become meaningless advertising
fodder.

That said, I am substantially more concerned about environmental issues
than many of my peers and acquaintances.

There are things that were commonplace in the old days (say, 35 years ago)
that I would not consider doing today. A few examples: dumping used motor
oil into soil as fence line weed killer. Gasoline as parts wash, then
dumped on the fence line as weed killer. Venting freon to the atmosphere,
both to repeatedly refill leaking systems and for actual repair.

As far as necessary use of chemicals (and other goods), I want products
that work. If there are choices that are truly better for the biosphere,
and the purchase cost different is not too great, I will go with the "bio
friendly" option.

--
Tony Sivori
Due to spam, I'm filtering all Google Groups posters.

tnom wrote:
Tony Sivori wrote:
Do you have a bottle of Spray and Forget handy? If so, would you please
post the listed active ingredients from the label?

Benzylkonium Chloride

From Wiki: http://en.wikipedia.org/wiki/Benzalkonium_chloride

It is used in pharmaceuticals such as leave-on skin antiseptics,
hygienic towelettes, and wet wipes, Lysol and ethanol-free solutions are
often used in preparations used for skin disinfection prior to use of
syringes.

Thanks for that. One more question (that I should have asked the first
time), what is the percentage listed on the label?

--
Tony Sivori
Due to spam, I'm filtering all Google Groups posters.

On Thu, 26 Nov 2009 19:56:15 -0500, wrote:

I had new roofing installed (GAF 50 year asphalt shingles) about 5
years ago. I've noticed that over the past year its started to
develop growing moss and algae on certain sections which are located
under tall oak trees. The old roof, under the same trees for 30 years
had NONE of this growth. I've also noticed that on one side of my
house, the same end of the house with the roof moss, has algae growing
relatively significantly on my white alum siding. Again, only the
past year or so.

This side is south facing and there are no side trees blocking
horizontal sun exposure.

So, my questions a

What might be causing this condition starting only this past year?

What damage is being caused by the moss on the shingles?

What could I do to eliminate and prevent future growth?

Any possible recourse with the shingle manufacturer?

Thanks for any/all advice provided.

B

I used the product "Shingle Shield" which are zinc strips installed
near the roof peak, that was nearly 20 years ago. Today there are
shingles made that release metal ions. For existing conditions you
might try a moss/algae killer product (hardware store, HD, Lowes).
Increase the sunlight and airflow to your roof (remove a tree or
two?). Increase your roof's pH. Decrease moisture--Check
drains/gutters. Your trees are probably giving you a lot more shade
than 5 years ago.

Tony Sivori wrote:
tnom wrote:
[attributes restored]
Tony Sivori wrote:
So I took a chance, and sprayed a weed killer on it one afternoon when
heavy rain was forecast for that night. It looks to have killed about
90% of it. But since I don't know what that might have done to shorten
the life of the shingles, I don't recommend doing what I did.
I thought you were concerned with Eco-Friendly products? Or is it just a
concern when others use them?

I don't know where you got that idea, given that I've never posted my
position on that topic.

So many companies greenwash their product that the "green" or
"Environmentally friendly" tags have become meaningless advertising
fodder.

That said, I am substantially more concerned about environmental issues
than many of my peers and acquaintances.

There are things that were commonplace in the old days (say, 35 years ago)
that I would not consider doing today. A few examples: dumping used motor
oil into soil as fence line weed killer. Gasoline as parts wash, then
dumped on the fence line as weed killer. Venting freon to the atmosphere,
both to repeatedly refill leaking systems and for actual repair.

As far as necessary use of chemicals (and other goods), I want products
that work. If there are choices that are truly better for the biosphere,
and the purchase cost different is not too great, I will go with the "bio
friendly" option.


Careful, a reasonable opinion like that could get you kicked out of here.

--
aem sends....