Ralph wrote:Grace is garbage, being familiar with the latest technology you
should know
this and not bring that name into the subject. You are 100% wrong in
assuming double coverage felt will stop ice from creeping under it. That
statement is laughable even by those that don't know much about roofing,
those with a little common sense would even know that. I take it you're one
of those weekend warriors, since your knowledge is lacking.



I suggest you look at a shingle to see if there even IS a tar strip on the
backside. Felt is laid just for the reasons I stated. Hope this helps. Tom

I suggest you look what is holding the cellophane on the back of shingles,
guess what that substance is? And yes the tar strip melts when heated, and
creeps from under the cellophane, which in turn sticks to the felt or roof
deck if felt is lacking.

If you need any knowledge you want to pass on, so you don't look like such a
fool. Just ask and you shall receive. No charge for roofing 101 course
today.

Well, enlighten me. Grace was the first stuff I saw come down the pike, and
serviceable but slippery it was. However, I've been out of the business for
about 10 years, so whatever's happened to their reputation is a mystery to me.
That little piece of cellophane on the back is only there to keep shingles from
sticking together in the bundle. and I don't believe it would creep at all when
the roof heats up. Again, I've torn off a few roofs, and might have missed
looking for the "creep", but all that was holding the shingles down were nails
or staples. Unless some fool used tar behind a chimney or something. Perhaps
the words "perfectly well" (referring to felt stopping an ice dam) were the
wrong ones to use, (just how fast will a nail leak through 30 lb.doubled?
(Rhetorical question.)) so I'll say "darned well". But how soon we forget the
ways things used to be done, and done successfully. If the causes of ice
damming are left untreated. the eave shingles will experience something like
"frost heave" over a number of cycles, rapidly accelerating their degradation.
A properly ventilated/insulated attic _needs_ no_ barrier_ at_ all_. Sorry to
have ruffled your feathers, but I've installed machine-cut cedar on pitches as
low as 6/12 with no barrier, and no damming . Perhaps with today's shoddy/cheap
builders, the first roof probably _needs_ a barrier, but by the time you find
out, the damage is done. Damn I'm long-winded. Again, sorry to have ruffled.
Tom

Someday, it'll all be over....