Subscribe or Renew Membership Subscribe Renew

24 ft span floor joist

JOHNNYPO's picture

I am building a loft in my barn, it will be 24 foot wide by 60 foot long and 7 feet tall.  I was trying to keep the middle span open underneath the loft.  I was planning on using 2"x12"x16' joists, they would overlap by 8 ft in the middle.  I was going to use 4 bolts, nails and heavy duty adhesive.  I am afraid of having spring in my floor, does anybody know where I could find engineering specs on attempting this.  I do not want to go this road if it is unsafe.  The lumber will be bought at Home Depot or Lowes in MD, I think it is mostly douglas fir.

Spring? Spring would be the (post #215996, reply #1 of 2)

Spring? Spring would be the least of your problems. The floor would be a trampoline.  You couldn't  store a case of tissue paper up there.  Floor trusses or laminated beams would probably work but you'd need an engineer to tell you.

Florida Licensed Building Contractor, 50 years experience in commercial remodeling, new homes, home remodeling and repairs and all types building maintenance.

Go to either of those (post #215996, reply #2 of 2)

Go to either of those suppliers and talk to the commercial desk.  They should be able to spec Trus Joists (Brand name for I joists) that will span 24'  likely looking at 12" on center though.  11 7/8ths TJI 560's at 12" on center will span 26' at 40 pounds live load and 20 pounds dead load.

if you can go to 14" they wont have a bit of a problem...ones I see at 14" 16" on center show a span of 23"6"

and a bonus...they might actually be cheaper than two 16' 2x12