Ceiling Joist question

[leeport]

Am building a 20x20 foot shop. My city code references the 2006 International Building Code. The span of my ceiling joists needs to be 20 feet. I cant find 20 foot 2x8's for my ceiling joists.

The Code says this about ceiling joists.

2308.10.4.1 Ceiling joist and rafter connections.

Ceiling joists and rafters shall be nailed to each other and the assembly shall be nailed to the top wall plate in accordance with Tables 2304.9.1 and 2308.10.1. Ceiling joists shall be continuous or securely joined where they meet over interior partitions and fastened to adjacent rafters in accordance with Tables 2308.10.4.1 and 2304.9.1 to provide a continuous rafter tie across the building where such joists are parallel to the rafters. Ceiling joists shall have a bearing surface of not less than 11/2 inches (38 mm) on the top plate at each end.

My question is, I cant find a method to join 2, 2x8's to get a 20 foot span. And also, would I join them at the center (10') or get a 16' and a 4'?

I am spacing the ceiling joists 24'' on center (same as my rafter spacing), so I can nail them together like the code specifies.

Any help in how to pass code with attaching two 2x8's?

thanks!
Jeff

 

[mike_81]

i dont think you should join them at all without vertical support underneath.

 

[38Chevy454]

Why not just use standard engineered trusses? They will have the span worked out and no concerns. Am I missing something here that seems the simple obvious solution?

 

[Zeke]

I guess you're looking at box stores for lumber because any lumber yard worth their salt will have 2 x 8 x 20's.

No, you don't splice them unless you overlap them something like 4 to 6' in each direction and bolt them together. Then they become too heavy for the 20' span.

 

[grumpygator]

Are you building your own trusses ?
***********G***********

 

[jerryd68]

Another option is is 2 X 8 LVL they come in length's up to 48' long.

 

[leeport]

Why not just use standard engineered trusses? They will have the span worked out and no concerns. Am I missing something here that seems the simple obvious solution?

I already have a ridge board with rafters attached

I also noticed in your garage build pics that your truss (ceiling joist part) is joined with side nail plates, or hammer plates as some are called.

 

[leeport]

I guess you're looking at box stores for lumber because any lumber yard worth their salt will have 2 x 8 x 20's.

No, you don't splice them unless you overlap them something like 4 to 6' in each direction and bolt them together. Then they become too heavy for the 20' span.

Good point. I will check with the local pro yard. I tried calling them last week but the line was constantly busy, and today is holiday.

I hope they have them, that will solve the issue.

 

[Tim The Tool Man]

I guess you're looking at box stores for lumber because any lumber yard worth their salt will have 2 x 8 x 20's.

No, you don't splice them unless you overlap them something like 4 to 6' in each direction and bolt them together. Then they become too heavy for the 20' span.

^ This! Any true lumberyard will stock them. Far cheaper than an LVL and besides you'll probably have to got to a real lumberyard for those LVL's

Any mid sized town will have at least one lumberyard somewhere...

 

[brewchief]

Ceiling joists and rafters shall be nailed to each other and the assembly shall be nailed to the top wall plate in accordance with Tables 2304.9.1 and 2308.10.1. Ceiling joists shall be continuous or securely joined where they meet over interior partitions and fastened to adjacent rafters in accordance with Tables 2308.10.4.1 and 2304.9.1 to provide a continuous rafter tie across the building where such joists are parallel to the rafters. Ceiling joists shall have a bearing surface of not less than 11/2 inches (38 mm) on the top plate at each end.[/B]

My question is, I cant find a method to join 2, 2x8's to get a 20 foot span. And also, would I join them at the center (10') or get a 16' and a 4'?

I am spacing the ceiling joists 24'' on center (same as my rafter spacing), so I can nail them together like the code specifies.

Any help in how to pass code with attaching two 2x8's?

thanks!
Jeff

I don't believe you are allowed to splice ceiling joists unless they are supported.

 

[leeport]

Just an update, I found 20 foot 2x8's at the good lumber yard in my area. Thanks for all the help. The ceiling joists are up and nailed. Sure makes the space look smaller now that they are in.

 

[pattenp]

You are not planning to use the space above for any storage are you? 2X8's with a span of 20' on 24" centers has no load capacity other than to hold up a drywall ceiling.

 

[IONH]

You could also have run 2x8x10's (more likely cut down 12's) to lap next to each other and put an LVL across above them using a beam on each end. That's basically like having a wall below as the joists would be hung from the LVL.

I had researched removing a section of wall in the center of my split and this is what an engineer wrote up for me.

 

[Paultergeist]

This is possibly a dumb question, but what is a "LVL?"

 

[Stuart in MN]

This is possibly a dumb question, but what is a "LVL?"

Laminated Veneer Lumber. There's an explanation here: http://en.wikipedia.org/wiki/Laminated_veneer_lumber

 

[theoldwizard1]

Am building a 20x20 foot shop. My city code references the 2006 International Building Code. The span of my ceiling joists needs to be 20 feet. I cant find 20 foot 2x8's for my ceiling joists.

The Code says this about ceiling joists.

2308.10.4.1 Ceiling joist and rafter connections.

Ceiling joists and rafters shall be nailed to each other and the assembly shall be nailed to the top wall plate in accordance with Tables 2304.9.1 and 2308.10.1. Ceiling joists shall be continuous or securely joined where they meet over interior partitions and fastened to adjacent rafters in accordance with Tables 2308.10.4.1 and 2304.9.1 to provide a continuous rafter tie across the building where such joists are parallel to the rafters. Ceiling joists shall have a bearing surface of not less than 11/2 inches (38 mm) on the top plate at each end.

My question is, I cant find a method to join 2, 2x8's to get a 20 foot span.

To the OP

You missed the part I highlighted in Blue. That "partition wall" is not a load bearing wall !


Just interested. Did any of the yards have 2"x10"x20' ? Most places can order dimension lumber up to about 30' (although it will probably be Douglas Fir and cost and arm and a leg). Wood I-beams make good ceiling/floor joists and are a lot lighter and easier to handle. LVLs usually don't come into play unless you need to carry a really BIG load.

 

[leeport]

You are not planning to use the space above for any storage are you? 2X8's with a span of 20' on 24" centers has no load capacity other than to hold up a drywall ceiling.

nope no storage in the attic.

 

[leeport]

To the OP

You missed the part I highlighted in Blue. That "partition wall" is not a load bearing wall !


Just interested. Did any of the yards have 2"x10"x20' ? Most places can order dimension lumber up to about 30' (although it will probably be Douglas Fir and cost and arm and a leg). Wood I-beams make good ceiling/floor joists and are a lot lighter and easier to handle. LVLs usually don't come into play unless you need to carry a really BIG load.

I got it. I was able to find the 20' 2x8's. They are up and all nailed in. Sure makes a difference with how sturdy the building is now. I am a complete novice at this. I have built several small sheds but nothing this big. I have learned a lot during this build.

One of the things I learned that hit home more than anything, Framing is a young mans game. At 55 I thought I was half way bad-***. I am such a whimp, and I **** big time. I give so much respect to these guys who do this. They have nads much larger than mine.

Thanks for all the help!

 

[leeport]

One more update concerning live loads. I went up and checked my home attic. It's a 8-12 pitch roof and the garage is roughly 22x24. The ceiling joists are on 16 centers, and are 2x8's. The attic is decked mostly and I have been storing weights and benches and car parts up there, plus walking up there for over 23 yrs. It has no sag, no problems. Not even a crack in the mud and tape of the rock in the ceiling. This is not near what the International Code Council calls for, and all is well.