On Nov 4, 2:02*pm, gregz wrote:
bob haller wrote:
Once you begin to see that green stuff on your roof, that's an indicator
it's time for a new roof. *Replace it before winter or you will have
leaks.

up till a number of years ago no roof around pittsburgh had that wierd
discoloration, now every roof does that faces north. something big
must of changed.

if you believe every roof needs replaced the shingle companies will be
thrilled, at least around western pa its every home except those with
metal roofs

theres a company that advertises they clean roofs, i dont know what
they use but was told not to use bleach

My garage keeps getting blacker. The green moss that built up on my two
sheds, lifting the shingles, gets to a half inch thick. Those are both
under trees with complete shading.

Greg

Greg?

Where do you live, I've never seen moss on a roof that thick, only on
the north side of trees in a deep forest.