On Fri, 11 Nov 2005 12:32:57 -0600, Duane Bozarth
:> On Fri, 11 Nov 2005 09:57:28 -0600, Duane Bozarth
:> :> No, no I didn't go into all the details. They covered the skip sheathing
:> :> with 1/2" CDX plywood, then 30 lb. felt, then the shingles.
:> :Maybe that's the problem w/ the nailing...if they didn't fill in the
:> :open spaces in the former open decking they may not have had anything
:> :but the sheathing to nail to for some courses....which will leave any
:> :that are only nailed to 1/2" sheathing w/ not a whole lot of material to
:> :keep them there...
:> :My inexperience w/ solid decked roofs and composition shingles shows
:> :here...is 1/2" sheathing alone considered enough? (I've only had one
:> :house that had comp shingles and never had to do anything w/ the roof --
:> :everything else I have experience w/ is open decking w/ wood
:> I believe that 1/2" CDX plywood is code. The estimator told me that it
:> is ample and code even with my skip sheathing, which is approximately
:> 1x5 long boards nailed perpendicularly to the 32" on center rafters and
:> with on average about 5 inches space between the skip sheathing boards.
:> In at least two places a coupld of the skip sheathing boards are
:> actually touching, leaving more than a foot between two adjacent boards.
:> They could (and I thought probably should) have repositioned those
:> boards before nailing on the CDX plywood, but by the time I'd noticed it
:> it was too late. Presumably, the 1.25" roofing nails through the 1/2"
:> CDX is sufficient.
:If the nail is long enough to penetrate the nailing surface by 1/4" or
:so, any longer will make no difference whatsoever.
:32" rafter spacing? That must be pretty springy to walk on...
Yes, it's pretty springy. In some places it's a lot more springy than
others. It's kinda weird. It didn't feel near as springy to me before.
Before it had asphalt shingles over wood shingles, which were nailed to
the skip sheathing. I don't know how many layers of asphalt shingles
were on there. Funny thing is, there are a lot of nail heads sticking
out of the bottom ofa lot of the skip sheathing boards. The skip
sheathing is 1x5 inches and around 20 feet long. The house has two large
dormers, and on the north dormer (which has the lesser slope) there are
hundreds and hundreds of those nail heads sticking out about 1/4" from
the bottom. That makes me imagine that they did a tear off at some
point, probably of wood shingles and instead of pulling out or pounding
down all the nail heads, they pulled up the skip sheathing and turned it
upside down. Those nails are steel and are 1 3/16 inch.
I was thinking of adding some rafters to make them 16" on center, but
didn't. It would have been tough getting them cut right and getting them
in there and I wasn't sure about the installation technique.