Does anyone know if there is a minimum roof sheathing requirement in Indiana? I have a copy of the 2003 IRC and the only thing they say is a minimum of 5/8 inch on 24 inch rafter or truss spacing. I downloaded the 2005 Indiana Residential Code and could not find any mention of minimum thickness of roof sheating. Does anyone know the minimum for 16 inch O.C. rafters or trusses? I am asking because I was told by a person who claims to teach a class on code enforcement that 7/16 inch OSB is not allowed as roof sheathing in Indiana. I found this interesting because that is all the builders around here use. Thanks.
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I don't know the answer, but I do know that there are places in Indiana where the idea of government regulation of building is taken much more seriously than in the state as a whole.
So it wouldn't surprise me that somewhere in the state 7/16 inch OSB wouldn't be allowed, but elsewhere...???
Rich Beckman
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I would not use anything less than 5/8" under any conditions. The maximum span for my roof will never be greater than 16"o.c. It only makes sense. You are not going to save enough money to make a difference. Why cheat yourself???
up here I got 3/4 on mine....probably because of the darn old "lake effect snow".....
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oresti,
I've heard of areas that would allow 7/16" sheathing if "H" clips were used, otherwise 5/8" min. on all other apps. ( 16" or 24" O.C. ). If you check your sheathing, the span ratings are stamped on them, like this: x/x typically , the first figure is the roof rating in inches, the second the floor rating in inches, so for instance a symbol 32/16 would mean a max. distance between supports of 32" for roof sheathing and 16" for sub-floor sheathing.
I would use 3/4" in all situations, but thats just me.
Geoff
I have 7/16 flakeboard with clips over 24"OC rafters and skip sheathing (we used to have a shake roof). That's common here, but we don't have nasty old snow. - lol
So far this year, neither do we! :)
Geoff
I put 3/8 plywood sheathing on 16" centers on the chicken house. I think it would be a lot better with 2 or 3 more 8ths thickness. Seriously weak feeling when walking on top. I have 5/8 on the house.
Mark,Re: "Seriously weak feeling when walking on top."The chicken house is for chickens to walk on top of. You stay on the roof of your own house with the 5/8" sheathing and you'll be just fine. No need to thank me. :-)Bill
I was afraid I would fall through. You really dont want to be injured and laying in chicken ####. That there is some nasty ####!
This is pretty typical for BT: you got 8 opinions but nobody gave the answer to your simple and direct question: "Does anyone know if there is a minimum roof sheathing requirement in Indiana?" I don't know the answer either, but here is a question: Is the 2005 Indiana Residential Code based on a model code? Like maybe IRC2003 or IBC2005? It will probably say right in the front of the book. If so, the Indiana code still has to be consulted to get the answer, but someone who does not have the Indiana code but is familiar with the model code in question could tell you what paragraph(s) and/or table to look at.
Further it would seem that the person who first told you that 7/16 inch OSB is not allowed as roof sheathing in Indiana would be able to give you the page/paragraph/table with the info.
As far as the guys above who said use 3/4", I'll bet you $1,000,000 that these guys aren't new home builders. Maybe subcontractors or remodelers, but definitely not for-profit new home builders.
as far as my roof is concerned..the roof was new and definately not installed by me or anyone here thank you very much !!it was merely my 2¢.....oresti doesn't say where in Indiana , and that's probably why he got the answers he did.....BTW I'm a sparky....
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.Imagination is more important than knowledge.....
Albert Einstein..........Wer ist jetzt der Idiot
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Mark,
The Indiana residential code is based on the 2003 IRC. I downloaded the Indiana code and bought a copy of the 2003IRC. The only thing I could find was in the IRC, which stated, "5/8" minimum sheathing for 24" O.C. rafter or truss spacing. I thought it odd that the IRC didn't mention requirements if you have 16" O.C. spacing. Around here (west-central Indiana, Terre Haute area) lots and lots of people use 7/16 on roofs. Everything I can find says that 7/16 osb isn't allowed but the fact that so many people (even contractors) use it so I thought I was missing something. Doesn't sound like the building inspectors around here know the code. Thanks.
Michael
I find that interesting.
Usually the code defers to the manufacturers specs. 7/16" OSB or 15/32 cdx ply are both manufacture rated for 24" span for roofs as long as they are laid grain orientation perpendicular to the supports.
Not arguing what you found , or that it is in the code there, just an interesting thing to me.