will osb span a 4ft gap w/o excessive sag

[cyamaha2007]

I am building a 36x56 pole barn. I put my trusses on 4ft centers and they were designed with a ceiling load. I was going to install 2x4s to the bottom of the trusses to attach the osb to but money is tight. What do you guys think can i get away without it? I will be blowing in insulation on top of it.

 

[GeorgiaHybrid]

It will more than likely sag with or without insulation. It would help if you use clips but even then, it will probably sag quite a bit.

 

[1320stang]

I'd maybe use thick mil plastic and blow insulation on top of that. Then put 2x4's up later and whatever you cover it with.

 

[mypov]

It will for sure sag - excessively!
Put your 2x4's 24" on centre (perpendicular to your beams, of course), then install your insulation with vapour barrier, sandwich your vapour barrier between the 2x4's with 1x4 or better yet 2x2's (15" on centre, perpendicular to the 2x4's - this holds the insulation in, and will allow you to later install foam insulation if you wish) you can leave it like this until you have the money to add your OSB drywall or plywood. Will cost you less and will preform much better then having a 4' span with OSB. I've seen OSB sag at 24" on centre.

Best of luck.

 

[StillSmokey]

I wouldn't span on more than 24"oc

 

[Wanna Ride]

Will it sag? Like an old hag's ****!

Anything more than 24" is gonna have probs.

 

[Jack Olsen]

If money is tight, attach 1x2s instead of 2x4s.

 

[ibedayank]

can you afford to do it twice?



do it right the first time and be done with it

 

[mypov]

Yeah, you could also just strap your beams with 1x2's and not worry about the extra strapping....It'd be cheaper yet to buy 1x6's and rip them with a table saw into 1x3's, or 2x4's and put up your vapour barrier - you'll have to keep that 6mil poly really tight though else it will sag as well with the insulation if you're spacing the material you want to later attach your ceiling at 24" OC.
Good luck.

 

[Justanoldguy]

1x2 at 16" centres would be best.
Have done this dozens of times in the past with no sag.

 

[NUTTSGT]

can you afford to do it twice?



do it right the first time and be done with it

Some good advice there. If you cheap out now, it'll sag. After it sags, you'll be pissed at yourself for cheaping out when you did it.

 

[long handles]

Our local Lowes puts the "ugly" lumber people won't buy in bundles out front of the contractor entrance.

It's a hodge podge of 1 x material, 2 x material etc......

It ain't pretty stuff, but it'd be worth using for lathing the trusses to hang OSB from.

The material section of Craigslist isn't a bad place to buy some stuff cheap from either.

 

[jktruck150]

Yes it will sag...don't ask me how I know. Its an embarassing story.... just don't try it.

 

[Zeke]

If you guys are talking about running 1 x 2 flat on the bottom of the trusses as firring strips, that's not a lot to hold up OSB and insulation. 16" centers would be minimum in my book for a home, much less a cold damp garage. What would 3/8ths ply cost?

 

[cyamaha2007]

I found a place i can get a ton of 5ft 2x4s. I think ill stand them up between the bottom cord of the truss. id think that would be the strongest way.

 

[NUTTSGT]

I found a place i can get a ton of 5ft 2x4s. I think ill stand them up between the bottom cord of the truss. id think that would be the strongest way.

Smart man. I think you would be cussing yourself later if you didn't do it right the first time.


Here's what I did in my garage. I laid them flat as they're not really "structural" but only support the celing, it also gave me more of an edge to hit with the nailer since I put my ceiling up myself.

 

[cyamaha2007]

Thats exactly what i want to do but stand them up vertically. I have some heavy halide lights that ill be able to mount any where now intstead of just on truss layout.