On 1/28/2011 8:26 PM, RicodJour wrote:
On Jan 28, 9:04 am, Jeff wrote:

Nice weather for a change, so I'm tearing off half the roof and
reshingling. I've avoided reroofing this because of the 3 to 6 layers up
there!

That's only a few more layers than the maximum you're supposed to
have. I don't think I've ever seen more than four. Maybe that's
because after that the roof tends to sit down on the job!

Yeah, I know. Everyone who looked at it says: "Wow." I've previously
down good bits of it, mostly on the side with dog house I'm doing later.

snip

You're confusing some terms. Sheathing is the plywood or OSB.
Underlayment is either 15# (or 30#) building paper, or self-adhesive
membrane such as Ice& Water Shield.

I'm thinking of running the ice dam around all the edges and down the
valley, and then covering the remainder with 15# felt with some overlap
over the ice dam. Does that sound about right? Or should I run the felt
over the ice dam except in the valley?

BTW, I wound up using the plywood I had which I had on hand. One of the
Slims cut it up while I was picking up the shingles. There's a half
sheet of oak up there with some cheaper birch. Slaps head!@#


I'll be using cut valleys, which seems to be the norm here. Anything
else I should be careful of?

Follow the directions on the shingle bundles and it's pretty much a
piece of cake. Code usually defers to the shingle manufacturers'
instructions. The only places you'll run into some head-scratching is
around the dormer you mentioned in your subsequent post. Most likely
what happened with that doghouse dormer is that they didn't double up
the rafters at the dormer side walls, or even more likely, all of that
extra weight of those extra layers has exceeded the rafters' design
capacity.


This part of the roof I did long ago. It is only 1 layer. And I think it
is just one rafter for each wall. I'll post up questions on this later.
I've certainly thrown a lot of tar and shingle and flashing against
the dog house to little avail. Getting the water to run away from the
dormer is a better idea, I think. That and ice shield which I didn't
know about then.

Not sure if you realize how extreme you situation is, but
those extra layers are well beyond your roof design loads. Codes used
to allow three layers, and now most jurisdictions don't allow more
than one additional layer before you have to strip the roof down to
the sheathing.

BTW, you won't find a single shingle manufacturer that does not
require underlayment. If you omit the underlayment you automatically
void your warranty.

OK.

I think I did good with the shingles. 35 year Atlas Pinnacle (made here
in Atlanta last November, with algae protection) for $50/square. That's
better than I was expecting!

Thanks.

Jeff

R