Strange roof decking

[cbottger (Charley L. Bottger)]

xxxxxx

[wcollier (Wayne Collier, HI5099)]

What type of roof covering?

[cbottger (Charley L. Bottger)]

@wcollier

What type of roof covering?

Asphalt shingles

[jritter (John Ritter)]

[FONT=FranklinGothic-Demi][size=2][FONT=FranklinGothic-Demi][size=2] Roofs
[/size][/FONT][/size][/FONT][FONT=FranklinGothic-Demi][size=1] Laying Sheathing
[/size][/FONT][FONT=FranklinGothic-Book][size=1] Before installing sheathing, make sure the
[/size][/FONT][FONT=FranklinGothic-Book][size=1] framing
underneath is level and not twisted.
[/size][/FONT][FONT=FranklinGothic-Book][size=1] Add shims or blocking as necessary to cre[/size][/FONT][FONT=FranklinGothic-Book][size=1]ate
a smooth, flat surface.
Panels should be installed with the 8’ length
[/size][/FONT][FONT=FranklinGothic-Book][size=1] perpendicular to support members. When
laying out sheathing, make certain that each
[/size][/FONT][FONT=FranklinGothic-Book][size=1] panel covers at least two spans and panel
[/size][/FONT][FONT=FranklinGothic-Book][size=1] edges fall at the center of a support. It may
be necessary to trim some panels. Make
[/size][/FONT][FONT=FranklinGothic-Book][size=1] sure that the “This side down” stamp is on
the underside. Layout rows of panels so
[/size][/FONT][FONT=FranklinGothic-Book][size=1] that end joints are offset by at least one
[/size][/FONT][FONT=FranklinGothic-Book][size=1] on-center spacing of the supports.
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=7&ved=0CEwQFjAG&url=http%3A%2F%2Fwww.woodbywy.com%2Fdocument%2Fosb-4004%2F&ei=82M3U7CIOJPJsQTUx4HgDA&usg=AFQjCNEogV9En6VkehEmlDQe4PlHHHMsQA&bvm=bv.63808443,d.cWc
[/size][/FONT]

[cbottger (Charley L. Bottger)]

@jritter

[FONT=FranklinGothic-Demi][size=2][FONT=FranklinGothic-Demi][size=2] Roofs
[/size][/FONT][/size][/FONT][FONT=FranklinGothic-Demi][size=1] Laying Sheathing
[/size][/FONT][FONT=FranklinGothic-Book][size=1] Before installing sheathing, make sure the
[/size][/FONT][FONT=FranklinGothic-Book][size=1] framing
underneath is level and not twisted.
[/size][/FONT][FONT=FranklinGothic-Book][size=1] Add shims or blocking as necessary to cre
[/size][/FONT][FONT=FranklinGothic-Book][size=1]ate[/size][/FONT]
[FONT=FranklinGothic-Book][size=1]
a smooth, flat surface.
Panels should be installed with the 8’ length
[/size][/FONT][FONT=FranklinGothic-Book][size=1] perpendicular to support members. When
laying out sheathing, make certain that each
[/size][/FONT][FONT=FranklinGothic-Book][size=1] panel covers at least two spans and panel
[/size][/FONT][FONT=FranklinGothic-Book][size=1] edges fall at the center of a support. It may
be necessary to trim some panels. Make
[/size][/FONT][FONT=FranklinGothic-Book][size=1] sure that the “This side down” stamp is on
the underside. Layout rows of panels so
[/size][/FONT][FONT=FranklinGothic-Book][size=1] that end joints are offset by at least one
[/size][/FONT][FONT=FranklinGothic-Book][size=1] on-center spacing of the supports.
Redirect Notice
[/size][/FONT]

Understand but I am dealing with two layers of decking

[jritter (John Ritter)]

In this same article They talk Roof and wall have different aps. Two layers for wall.

[lkage (Larry Kage, CMI)]

@cbottger

Ok guys hows about a little info here as I have never seen this before and I was never a framing carpenter???

House constructed in 2011 with OSB roof decking running vertical with the rafters no H-clips installed visible from the attic, but from between the joints of the OSB I can see another layer of what appears to be ply wood can not tell which direction the ply wood is installed or how thick it is. Why would someone install two layers in this manner were they being stupid or was there a method to their maddness

On the back of the OSB there are arrows pointing vertical and stating strength axis

Vertical with supports, eh? Then, not the minimum of 3 supports (with the long dimension or strength axis) as indicated by the APA: http://www.schmeling.com/reference/pdf_files/plywood_span_ratings.pdf

The Span Rating on APA RATED SHEATHING panels appears as two numbers
separated by a slash, such as 32/16, 48/24, etc.
(a)
The left-hand number denotes the
maximum recommended spacing of supports when the panel is used for roof sheathing
with the
long dimension or strength axis of the panel across three or more
supports.
The right-hand number indicates the maximum recommended spacing of
supports when the panel is used for subflooring with the
long dimension or strength
axis of the panel across three or more supports.
A panel marked 32/16, for
example, may be used for roof decking over supports up to 32 inches on center or for
subflooring over supports up to 16 inches on center.

Were there plumbing vent holes or other vent holes, etc., that may give more info about the plywood on top. I’m not familiar with doing it like that, either.

[jritter (John Ritter)]

As with all thing, they are subject to change, but I was always taught to install plywood and OSB horizontal. never vertical.

[btoye (Bradley Toye, CMI)]

Was this on a hip section with step down trusses?

[cbottger (Charley L. Bottger)]

@btoye

Was this on a hip section with step down trusses?

Not a truss built all purlin supported Not a hip roof

[cbottger (Charley L. Bottger)]

@jritter

As with all thing, they are subject to change, but I was always taught to install plywood and OSB horizontal. never vertical.

Me toooo I always see it horizontal never vertical but never two layers

[jritter (John Ritter)]

And because it was two layers it was run opposing grain and size for maximum strength. Also was it nailed or screwed?

[cbottger (Charley L. Bottger)]

@lkage

Vertical with supports, eh? Then, not the minimum of 3 supports (with the long dimension or strength axis) as indicated by the APA: http://www.schmeling.com/reference/pdf_files/plywood_span_ratings.pdf

Were there plumbing vent holes or other vent holes, etc., that may give more info about the plywood on top. I’m not familiar with doing it like that, either.

I wished there had been the house was total electric with minimum plumbing vents just almost the same size as the hole could not see squat

[cbottger (Charley L. Bottger)]

@jritter

And because it was two layers it was run opposing grain and size for maximum strength. Also was it nailed or screwed?

Nailed

[cbottger (Charley L. Bottger)]

@lkage

Vertical with supports, eh? Then, not the minimum of 3 supports (with the long dimension or strength axis) as indicated by the APA: http://www.schmeling.com/reference/pdf_files/plywood_span_ratings.pdf

Were there plumbing vent holes or other vent holes, etc., that may give more info about the plywood on top. I’m not familiar with doing it like that, either.

Larry If I am reading correctly the Apa rating is 7 which would indicate it must be supported every 7 inches vertically do you agree

[badair (Barry Adair, EIFSTX#39)]

fly on the wall, wag

1. goofball installed decking wrong direction
2. someone paying attention pointed out the deficiency = no pay until corrected
3. “oh btw don’t even think of tearing it off, damaging it & my trusses to reuse correctly”
4. goofball had new material ordered and installed in the right direction = made a check
5. what isn’t seen is did the 2nd layer land on rafters correctly?
6. were there a lot of shiners?
7. what was the rafter spacing, appears over 24"?

[cbottger (Charley L. Bottger)]

@badair

fly on the wall, wag

1. goofball installed decking wrong direction
2. someone paying attention pointed out the deficiency = no pay until corrected
3. “oh btw don’t even think of tearing it off, damaging it & my trusses to reuse correctly”
4. goofball had new material ordered and installed in the right direction = made a check
5. what isn’t seen is did the 2nd layer land on rafters correctly?
6. were there a lot of shiners?
7. what was the rafter spacing, appears over 24"?

Your prolly correct I am going to bust him and see what happens. I am thinking what my obituary lines are going to say. When the hair on the back of my neck stands up there is usually a reason!!!

[jritter (John Ritter)]

@badair

fly on the wall, wag

1. goofball installed decking wrong direction
2. someone paying attention pointed out the deficiency = no pay until corrected
3. “oh btw don’t even think of tearing it off, damaging it & my trusses to reuse correctly”
4. goofball had new material ordered and installed in the right direction = made a check
5. what isn’t seen is did the 2nd layer land on rafters correctly?
6. were there a lot of shiners?
7. what was the rafter spacing, appears over 24"?

Yep!! That’s probably how it happened.

[badair (Barry Adair, EIFSTX#39)]

@cbottger

Larry If I am reading correctly the Apa rating is 7 which would indicate it must be supported every 7 inches vertically do you agree

it appears to be 24/16 see your rotated pic
thus my appears to be over 24" rafter spacing ?
that’s all you get for your BD until you answer me! :twisted:

[badair (Barry Adair, EIFSTX#39)]

@cbottger

Larry If I am reading correctly the Apa rating is 7 which would indicate it must be supported every 7 inches vertically do you agree

CB,
appears to be 24/16 see your rotated pic, that reads 24" on center for roof 16" on center for floor
that’s why i asked appears to be over 24" rafter spacing? there may be more wrong than right
Ms. Cleo’s hotline is open i’ll be on the job from now until 1pm today, call me
that’s all you get for your BD until you answer me! :twisted: