Framing question for the experts
 

By this time tomorrow I will have a 40x60 barn. It is not quite a pole barn, it has interior supports ten feet from each of the 60 ft walls with beams paralleling the walls. I want to wall in half of the building - a 40x30 space. It will be 30 feet deep, and the 40 foot dimension is a 20 foot open area with a ten foot space on each side that has a 10 foot ceiling now. I want to install a ceiling over the 20x30 foot area, so I will have to have something that spans the 20 foot open area to attach the ceiling to. I'm thinking trusses, but how do I size them? All they will be supporting is 600 square feet of drywall and some lights.
Suggestions?

Sounds like you're thinking of building trusses.
How much height do you have above where you want to have the ceiling?
If it is not too much, I would do a drop ceiling. supported from the rafters. Otherwise I would just call up the experts and have 20 'trusses delivered.
Best
Les

Wood I beams or web truss based on your description but I'm not sure I'm following the verbal picture you're trying to paint. You'll have a half section of the barn walled off. On each end of your 40x30 room will be 10' with a 10' ceiling. What I'm not following here is how high will the ceiling be for the 40x60? are you looking for loft space in the 20' section?

Can you post pics of the existing framing?

Are you trying to support this ceiling from the existing roof? Or are you building a 20x30 room?

If there's any possibility that you might store something above that space down the road, I would probably use I joists. You can find load tables online for those and dimensional lumber, so it's just a matter of figuring the dead and live loads and the span and picking something out of a table.

Photo is worth a thousand words.

Ceiling very much depends on plans for heating the space, do you want storage above it, does it need to be sound proof, etc....

Snap some pics.

Will do. I kind of jumped the gun here. Planning out loud. Give me 24 hours.

they make wood beams I or H out of glue laminated parts
kind of like a plywood beam as long as you want 20 ft eazy
I would think 2x4 8ft would be the cheap way to frame for dry wall
but need more beams if you want heavy storage overhead

The ceiling will be 10 feet high, and as stated will only need to support the drywall hanging from it and some lights. No loft or overhead storage. Pics of the building coming tomorrow.

2x8 #2 Doug fir on 16 inch centers. Put the crown up.

Maximum Span Calculator for Wood Joists and Rafters

https://www.weyerhaeuser.com/application/files/8215/1128/9314/TJ-4000.pdf

Finally got a photo of the building. What I want to do is built a clean room in half the 40x60 barn.
The space between the lofts on either side is 22' and I'll need a ceiling over that. I'm thinking 10 foot ceilings. Also cutting the building in half with a wall 30' in from the big sliding doors. Also replacing the sliding doors with a garage door.
Trusses (24') are $75 each at Menards - not bad, and I can probably space them at 4' since they only have to support the drywall ceiling. OTOH, after looking at the photo I'm thinking of running 2x8s across the 22' span and dropping 2x4s down from the existing trusses to support them. It's more work, and may not even save any money. Bad idea?

http://forums.pelicanparts.com/uploa...1514114457.jpg

You're going to want 2' on center minimum for supporting the drywall and then you'll want 5/8 drywall to do the ceiling. OR you could go 4' on center with 2x4's screwed to the bottom of the trusses at 2' on center still using 5/8 drywall. For the time it would take to do the 2x4's I'd just get extra trusses.

I like your 2x8 idea with 2x4's going up to the existing truss. Probably the least expensive way. I'd still go either 16 or 24 on center. I'd get four 2x6's nailing two sets of "L" I'd fasten those to the top of the new joists to act as a spacer and for support. You could put both L's up in place with the new joist location marked on each so as you're putting them up you'd be straight too. The two L's will keep them from sagging while you can then use each L to fasten your 2x4 supports to.
I hope all that makes sense.

Is the room something you're wanting drywall in for looks? If this is just going to be a room where you go to work or play around in a bit, why not just use metal? Then you could go 4' on center and the beauty is, no drywall taping.

There's a chart in the lit below for I joist sizing.
https://lpcorp.com/media/1381/lp-solidstart-i-joists-residential-technical-guide-canada.pdf

You have enough roof height in that building that sooner or later someone is going to want to put something on top of whatever ceiling you construct so I would use I joists and allow for a reasonable live load on top of it.

He would have some usable space no doubt, but he'd need to use a 16" I joist at about 16 OC for a free unsupported span like he'll have with a drywall ceiling. For less money I'd put 2x12's crown up as you mentioned earlier and still use the L brackets I mention above to run supports up to the existing truss.system.

I'm not a huge fan of using the existing trusses to support new loads, for a variety of reasons.

I would probably also put the clean room in the back of the barn, rather than divide it in half, but that's not my choice either.

I'm not familiar with the metal you are talking about.
If I'm going to allow for storage I may as well use floor trusses. They are cheaper and probably do the job better than a roof truss.

edit: Hmmm I-joists are cheaper yet and the do make them in 24' lengths.

Same here. TJIs or equivalent. Most 'real' lumber yards have access to design software or factory reps, and will tell you what you need.

Best wishes on the new space. Save room for a lift or 2.

By the time you go to a 14 or 16" I joist, how much room will you have on the upper loft level?.
Next question is, why are you lowering the ceiling from the original height? If it's for heating efficiency, I don't think lowering the ceiling 4 or 5 feet is going to be worth the expense of the I joists and work put into it. I'd spend that money on insulation and seal the space well and just keep the original ceiling height.
The metal I'm talking about is like the stuff on the outside of the building now. It doesn't look bad but if you're going for a more residential appearing space, it's not gonna work.

I'll have to do some measuring. I have plenty of storage and don't care about the space above the room.

Again, I'll have to do some measuring. I think the height is 16 feet but that's only what I've been told and no, I don't want to heat that. If I don't put some kind of structure up there I may end up with a drop ceiling. The garage door is going to be 8 or 9 feet high, so there is going to have to be some framing to hang it from if I do that.