roof osb thickness

[justin1795]

im planning on putting a pole barn up and sheeting it with osb and doing asphault shingles. I called they city to see requirements on thickness and they weren't very helpful. they said ask the builder. I said so is there no requirement? they said there is. I said well what is it and they said your builder should know. the trusses will be 4 foot apart more than likely.

 

[kd3pc]

My trusses are only 2' apart and I used 1/2" nominal with hurricane clips. Not sure I would use 1/2" on 4' centers...would go at least 5/8 with clips, if not 3/4"

If there is zoning or AHJ, make sure the markings are facing down in to the work space where they can "see" the stamps and clips.

Best of luck

 

[theoldwizard1]

My son had to pay extra to upgrade from 7/16" to 1/2" OSB when he had his roof re-decked. Clips are a must for any rafter spacing larger than 16" OC.

With 4' rafter spacing I would seriously consider 2x4 purlins under each horizontal joint.

 

[justin1795]

thanks

 

[Red05GT]

You will have to use purlins. Even 3/4" osb or plywood would not handle a 4' span.

 

[justin1795]

might be cheaper to look into adding truses

 

[Falcon67]

7/16" OSB will span MAX 24" with clips. Same AFAIK with the slightly thicker stuff. 48" is way too far.

 

[Broncoman75]

On houses (2ft truss spacing) we use 5/8" osb. if you have to use 7/16 then clips are required. I would suggest as others have said to run purlins or add more trusses.
If you were to do a metal roof, you don't need sheeting, just purlins to screw the tin onto and it should outlast shingles....

 

[Zeke]

You couldn't do this w/o purlins clips or not. AFA calling the city, they cannot give advice over the phone and usually won't give it in person. However, they often times have handouts of 'typical' building requirements. You will find span tables on these generic plans.

It's the old deal with inspectors, they will tell you all day long what's wrong but they won't tell you how to fix it.

Hey, Broncoman, took you long enough to chime in. Welcome to live chat.

 

[Kevin54]

My son had to pay extra to upgrade from 7/16" to 1/2" OSB when he had his roof re-decked. Clips are a must for any rafter spacing larger than 16" OC.

With 4' rafter spacing I would seriously consider 2x4 purlins under each horizontal joint.

^^^^This^^^^

Even on 2' spacing between rafters you can feel the flex when walking on the roof. I would put 2x4's down as stated to make it a rigid roof.

 

[finn]

Inspector told us 5/8" min in Michigan

 

[rburke65]

5/8" what....OSB or plywood, and over what spacing of truss or rafter? Not very explicit info.

 

[NUTTSGT]

might be cheaper to look into adding truses

That is what I would suggest, so they are 24" O.C. When I built the house garage, I used 1/2" OSB with clips, 24"O.C.

 

[finn]

5/8" what....OSB or plywood, and over what spacing of truss or rafter? Not very explicit info.

OSB on standard 24" truss spacing.

I haven't seen anybody use plywood on a roof for 15 years.

 

[justin1795]

On houses (2ft truss spacing) we use 5/8" osb. if you have to use 7/16 then clips are required. I would suggest as others have said to run purlins or add more trusses.
If you were to do a metal roof, you don't need sheeting, just purlins to screw the tin onto and it should outlast shingles....

the hoa wants it to look like the house. they had some steel roofing at the farm show that had texture to it but it was over 3x the price.

 

[Diesel Dan]

5/8" what....OSB or plywood, and over what spacing of truss or rafter? Not very explicit info.

Also consider his location. Michigan U.P., the snow load is more up there.

 

[finn]

Also consider his location. Michigan U.P., the snow load is more up there.

You got that right. I hope it's still standing when I get back in the spring. Spring may start in July this year.

 

[icenfire01]

I would add some trusses, they are relatively cheap. 24" OC with 1/2" osb on that. No hurricane clips, but probably should have, cheap insurance.

 

[icenfire01]

Don't forget about your ceiling, It will make life a lot easier when you put up a sheet rock or tin if your trusses are 24" oc.

 

[justin1795]

well I got some good news the HOA says a steel roof is ok. so when doing the steel roofing are most guys putting sheeting underneath?

 

[Diesel Dan]

well I got some good news the HOA says a steel roof is ok. so when doing the steel roofing are most guys putting sheeting underneath?

I did, much quieter and with 100% support it is much less likely to be damaged by hail.

 

[Bib Overalls]

To my eye metal looks better over sheeting with felt in between. Subtle but discernible.

Neighbor across the road used 7/16 OSB on 24" spaced trusses. Spec grade shingles. I can make out every sheet of OSB. It dips between the trusses. We used 5/8 and premium architectural shingles. Flat as a, well, board.