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On Wed, 11 Nov 2009 20:53:16 -0500, "Kerry L." wrote:
Sir, I know what the granules are for. They serve 2 or more purposes -
slowing down the water as you state is their SECONDARY purpose. at
best. The primary purpose is to protect the "fabric" of the shingle
from sun and weather damage. When the granules dissapear, the felt
backing of the shingle is soon gone as well. Another MAJOR purpose of
the ceramic granules is to provide fire resistance. If you do not
believe me, see: http://www.nrca.net/consumer/types/asphalt.aspx
My point was about placing an obstruction in the path of water flow. I
don't want to get off topic taking it how a shingle is constructed. Heck,
we could go into opacity of the granules as well, but it has absolutely
nothing to do with water flow.
I also know what step flashing is, and how it is installed here.
Step flashing is fully coated on the bottom side with roofing cement
and nailed down at the top edge, then the shingle is placed over the
flashing and sealed down with roofing cement. The shingles are cut to
leave roughly 1/2 inch gap between the end of the shingle and the step
flashing. The next step is then placed over the shingle, with the
metal tab extending JUST ABOVEwhere the bottom end of the next shingle
tab will end. (Up to 1/2 inch of step flashing MAY show below each
shingle tab, but I prefer to see NO flashing showing beyond the
shingle.)
It is done this way here to prevent the shingles from lifting off the
step flashing in high winds and to seal the flashing to the roof. It
is generally only nailed to the roof deck, making it possible to
remove and replace step flashing when replacing a roof without
disturbing the aluminum or vinyl siding most commonly used on the
upper floor walls and gable ends of houses here.
The roofer who installed the first replacement roof on our house
(before I bought it) did not seal the step flashing and we had a leak
down the wall that dripped out of the door between the house and
garage when it rained within a year of us buying the house.
We replaced that roof - my father who worked for many years in
construction, along with several experienced friends and myself. When
Dad saw how the step flashing had been installed (it was exposed to a
large degree ) he said the guy who installed it should be shot.
The new step flashing was installed with fibrated plastic roofing
cement on both sides - and it never leaked again. Used just over a
quart of cement between the step flashing above the garage and the
chimney flashing.
No, but you created a problem when you go to replace that roof. If you
_must_ use some existing flashing, you'll have a heck of a time trying to
get it unstuck. More is not better. Your analogy would be similar if
someone were to say, just spread tar all over everything. It never leaked.
There's a correct way to flash, and the way your father did it. Sorry, but
professionals would never do it the way your father did.
Wow, what a nightmare, especially if one would to have stucco siding, as
the link you provided.
When the shingles (first generation fiber-glass -( not the best
quality stuff although it was "high end" at the time) started to crack
and curl after loosing much of the granule coating, I paid a roofer
(who did the roofing on many of the houses my Dad worked on over the
years) to do the job with laminated architectural shingles and
specified I wanted tar paper on the whole roof, and the step flashing
cemented. He said most people don't do it that way any more because it
costs more. "how much more?" I asked him. He said MABEE $200. I said
$200? DO IT!!!" He said he wished everyone thought that way -
Yep, you live in an area without strict codes. I have never worked an area
where felt was an option. No doubt why you get away with certain methods.
See http://www.renovation-headquarters.c...shing-wall.htm for
confirmation that I am not the only one who thinks this is the right
way to do it. And no, I didn't write it.
http://toolbelt.buildiq.com/tool-doc...epFlashSBS.pdf also
shows the same method but does not mention the roofing cement.
Also see http://www.youtube.com/watch?v=rzOn_8t4mZ4
The problem with the first site you provided is, they appear to be
"experts" from vacuums to software & everything else. I really hope you
don't think this site would convince me or anyone else besides yourself, to
take them seriously.
The problem with the second site you provided is, someone cut the step
flashing too short, and forgot about the starter strip. I don't believe in
regulating the internet, but stuff like this shouldn't be allowed.
The problem we see with GAF, is they don't even recommend using a second
layer of protection at step flashing. Such as a small bead of sealant along
the hidden edge, let alone _embedding_ step flashing in cement. Of course,
they are using a 10"x7" step flashing, instead of standard size. As I said
_B/4_, around here condominium associations _require_ all apron flashing to
be covered by roofing material. Put some thought into this one, there is
no doubt water will be trapped. By shingling over the flashing, you depend
on the sealant to be you first & _only_ protection from intrusion. Water
will sit trapped, until it evaporates or takes the course of least
resistance.
It's your roof, there's plenty of people to take your money. Unfortunately,
you will find them.