"Jimmie D" wrote in
:


"jp" wrote in message
.
.. On Mar 7, 4:45 pm, Dottie wrote:
I live in FL where algae growing on the roof is a big problem. When I
had a tile roof I had it sprayed every year with some kind of
mildewcide....a man comes around and does several houses in the
neighborhood. Last June I got a new GAF ultra Timberline shingle roof
that is supposed to be pre-treated with some kind of chemical to keep
algae from growing. So, when the man came around I said I wouldn't be
needing the treatment anymore. He said the stuff that was used to
pre- treat roofs didn't really help and I should go ahead and let him
treat mine. I didn't .. because I was afraid it might affect the
warranty. I called the contractor who said I didn't need anything
else and I e- mailed GAF while waiting to hear from contractor.
Haven't heard back from them.

Thing is, there are several houses around me who have newish roofs -
older than mine but not a lot older - and they are beginning to show
dark spots in places. Now I am wondering if I should call the guy
back and have him treat my roof before I get spots ... Anybody know
whether the GAF anti-fungal properties really work or not? Thanks.

Get in touch with a good roofer and ask him to install a copper strip
across the peak of the roof on both sides of the roof and when it
rains the copper will react and stop mildew, it works, good luck henry
penta, i seen this on the, this old house progran.

That what my father in law used to have on his house. When he got a
new roof they didnt put one back up
saying he didnt need it with the new shingles. Well he didnt for about
4 or 5 years, then he started to spray the roof with copper sulfate.
He more or less covered the whole roof with it but Ive heard yu can
just spray it up on the ridge.

Jimmie



A lot less expensive will be zinc strips. They sell them specifically
made for this. Half nailed under a shingle lip and half exposed.

There are other versions but it's zinc.

If you ever noticed a soiled dark roof that has metal vent stacks. From
the stack down it's not dark. Stack is galvanized. Galvanizing contains
zinc.