What do you guys use for your roof sheathing and why? 7/16 or 5/8ths? Would you consider 7/16 with clips the same as 5/8?
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I consider 7/16" for framed 16" OC
And 5/8" prefered
Welcome to the
Taunton University of Knowledge FHB Campus at Breaktime.
where ...
Excellence is its own reward!
You can get away with walking around on 7/16" OSB roofs??? 9 times out of 10 I end up down stairs...
Plwood or plywood in 5/8 works well....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
You caught that huh?
I said I cosidered it is all. Fact is, I never have and never would use OSB on a roof in any thickness. Advanterc or ply is fine by me.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
I''ve never used Adventec but from what everybody here says about it it is worth considering...
and I can not safely walk on an 7/16 OSB roof even at 16OC... I break thru... That gets rough on everything and I don't care for the adrenilene rush...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
You can walk on 7/16" OSB when spaced at 24" o.c. Prior to my getting a job here at the Building Department, the previous inspectors were allowing 7/16 OSB on roofs with 24" o.c. spacing. I guess they did not realize that the code does not allow 7/16 on roofs with our 50 psf snow load. We are now requiring 5/8" ply or OSB span rated 40/20 or 15/32 OSB or 1/2" ply span rated 32/16 with clips. These are all approved for our 50 psf snow load. Your local environment will dictate what is approved.
I will not get on an OSB roof...
PERIOD....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Are you THAT big?
300+
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
I just did a 5 in 12 roof over a new deck walkway in Sierra snow country. I used 3/4 ply and clips on 2' o.c. rafters.
I am a chronic overbuilder and I thought I was way over code but the inspector said it just made the #250 lbs per square foot "100 year storm" snow load requirement. Shows what I know. I would say 5/8 would be a minimum and for 5 in 12 or less I would go thicker if you are in snow country.
Thinking of starting a chapter of "OA" = Overbuilders Anonymous.
"It's been 3 days since I last used 12d's when 8d's would be fine...."
Cheers
Wylie
Success = Work+ Risk + Luck, in that order. Muriel Seibert
Was he commenting on the sheathing, the framing, or the whole roof system - and which part is it that just barely passed, or the whole?
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
319 in my suit and now add that same gear to my butt... When I get too near an edge is the problem, not the center..
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
OK, let's get real here - You are dressed, wearing the tool belt, carrying a sheet of ( PLY?) and sopping wet from rain and sweat.
now what do you weigh?
LOL
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
A little more than an express freight elevator headed for the basement...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
So THAT'S where they keep old express freight elevators! In the Bomb shelters
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Heading to the ridge with a bundle of shingles. In the blink of an eye, my left leg was through the sheathing to just above the knee ("Jason, I think I found a bad spot!"). Nasty particleboard crap they'd used as sheathing (didn't even look like OSB) had gotten wet. The main roofer dude had pulled off 3 layers of shingles. HO didn't wanna spring for new sheathing and was unhappy that the 3 layers of shingles had to come off (he figured they'd make the roof more waterproof).
I had to wack the pb with a hammer to widen the hole to get my leg back out. This was one of the spots the ho didn't have a choice in replacing the sheathing. Surprisingly, I didn't even get a scratch (or bruise) from breaking through. Smart a## roofer suggested I walk over the whole roof to find any other bad spots. His scrawny self was maybe 5'6" and skinny as a rail (although he could carry his weight in shingles) and scampered up a ladder like a squirrel going up a tree.
Roofers are a breed all their own.
jt8
I haven't seen very many shingle layers more than 5'8" amdf wiry!
I was once hoistuing a bundle to drop over the ridge to loosen them up when I stepped back for ballance and muy foot found a vent hole that some fool had papered over. Try running your leg through to the crotch with a bundle over your head!
Yes, I drew blood
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
He was commenting on the sheathing - basically that with the quality of plywood he thought 3/4 (which is actually 23/32") was necessary. I think he was "downgrading" the span capacity of the 23/32 CDX when he did the math.
I pointed to the APA "rated for sheating" stamp on the adjacent 1/2" wall sheathing "doesn't this mean anything?"
He's kind of a PITA (I think he's trying to make up his own more stringent code) but you can understand why when you see the snow you can get in the Sierra. In more than a few cabins you can't open doors in the gable ends during the winter as the snow sitting on the roof racks the entire structure. Doors will open again as soon as the snow melts!
Wylie
Success = Work+ Risk + Luck, in that order. Muriel Seibert
I worked in places in CO with 110# snow loads
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
What about OSB for wall sheathing? In fact, what about OSB, period?
do you mind if I ask what you weigh?
Nope....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
300+
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Nice dog; the name truely fits.
I never met a tool I didn't like!
Then you better start on a diet real soon!
how much do you think I need to loose????
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
I am going to put a new 7/16 OSB deck on the old farm house. On one side it's going on top of a true 1 inch oak deck. The other side has 1x6 purlins with a 6 inch gap between them so the old wood shingles could breathe.
You're a better man than I, if you can drive 16d common nails in old oak. So I am planning to use flutted masory nails ( hardened steel ) to secure the OSB.
Is 16d long enough or too long?
How many nails per sheet? Considering there's a deck under the new deck do all the nails need to be into the rafters?
If the answer is 8 on the edges and 6 in the field, is that the same as 28 nails a sheet.
dave.. 16d is too long... anything that sticks thru the undersheathing more than 1/4" is too long..
you could try teco nails .. say a 2".... they are pretty hard .. should be good for that seasoned oak..
but.. me. i'd beg, rent or buy a framing gun to nail it off..Mike Smith Rhode Island : Design / Build / Repair / Restore
Amen dude.
I'd srew it before id hand nail it if i didn't have my staplers..
If you want to read a fancy personal signature... go read someone else's post.
Staples!?!
did U come back here just to start a fight?
;)
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
I'd use srews to hold it down myself.
Long enuf to go through the sheathing and an inch into the framing except where it hits field only between frame.
Enough of them to hold it down, similar pattern to a newly nailed deck, tho obviously modified to the location of your sheathing and purlins.
A downside of OSB, even with good base for structure under it like that, ( even IMERC could walk on it with that oak underlying it) is that any moisture of any kind - from leaks or condensation or ice damns, will cause the edges to swell and telegraph through asphalt shingles.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Well, I use plywood exclusively, hate clips, and mostly use 5/8" for residential on 16" centers. I'll use 1/2" ply on something like a small shed or chicken house roof.
I built a house last year that spec'd 3/4" ply on 16" centers, which was probably a little overkill but it felt nice and solid between rafters, for whatever that's worth.
And I also built a garage onto a manufactured home last year, using my usual 1/2" wall sheathing and 5/8" roof sheathing....and the MH I was marrying the garage to had 3/8" OSB roof sheathing on what they call rafters on 2' centers!
So maybe it's whatever you're comfortable with!
5/8" cdx fir is my choice for 16" o.c. Its just a real solid roof especially when doing over lay valleys and dormers
5/8" OSB minimum, would not use anything less.
Remember when 1/2" plywood was 5 plies?
i used to use 1/2 cdx ply with clips for roofs framed 16" oc.. and 5/8 with clips for roofs framed 24" oc..
now, with our new wind requirements we will be using 5/8 T&G Advantech exclusively.. because if we don't , we have to block every seam within 4' of the perimeter.. including the top both sides of the ridge if we slot for ridge vent.
Mike Smith Rhode Island : Design / Build / Repair / Restore
5/8 tounge and grove advantech. No need for clips. I had this stuff exposed for year to the element s of upstate NY and it only gayed slightly wtih no buckling or peeling. It is expensive but well worth the investment. I wil never use anything else for roofing.
I love this thread.
blue
Good thread you started. "This may be a dumb question, but..." doesn't it depend on the pitch of the roof? I did my house with a 12/12 pitch with 1/2 CDX. It seemed plenty solid when I was shingling with the help of my BIL's who are tall and heavy. Now I am planning an addition with a shed roof pitched at 4/12. I'm guessing that 1/2 (7/16) might be OK for a steep snow-shedding roof, but not for a roof with less pitch and therefore more snow load. Rafters are 16 OC.