Floor joist spacing question

[peter gagliardi]

Trust me, there is bounce.
I build houses for a living. You cannot detect bounce by yourself very easily.
Go to the middle of those spans with another adult, have them jump, report back.
I try not to use them, but every job I have visited that does, exhibits the same. These are installed per engineers specs.
Solid lumber does not do it nearly as much.

[peter gagliardi]

Frank, I am not convinced. The engineering used is mostly only to cover deflection- span cannot deflect more than 1/480 . The I joist will ultimately fail under less deflection than solid lumber, they are not good in fires, and they do not take shock load well at all.
Oh, and I forgot, they do not do point or concentrated loads well at all.

Solid lumber is forgiving- yes it will deflect more, but catastrophic failures are less frequent beyond the specs.
Engineers are smarter than me, so who am I to argue.

[Steve Milito]

Hello folks, new here and couldn’t find an answer in the search. I’m building a 20x26 shop, wood floor, 2x10 PT floor joists with 1 1/8” advantech flooring. Max span of 2x10’s is 9’6”. Load will be of a typical wood working shop, heaviest items will be a lathe and table saw. Floor will be beefed up under the lathe.

Here’s my question. Will the floor joists 24” OC be sturdy enough?

Thanks, Bo

I started with an on-line "barn" plan when I designed my shop but wanted to have it modified in a significant way; it was 40'x35'. My builder recommended a local engineer, who I used. His approach was "I can make this like a factory but it's going to cost a lot or you can put it on slab. We then went through the whole what's going in it conversation and I basically gave him a list of dream equipment (a full sized lathe, full sized sliding table saw, etc). What we came up with as middle ground was 2x12's on 16" centers and 12' spans. We also used 1 1/8 advantech flooring. There's a system of piers and girders underneath to support it all which is every bit as important as the joist spacing. I believe that live load rating was in excess of 175 lbs/ft^2. I hope that helps.