Mezzanine

[sandslot]

I am building a mezzanine that will be 20'x24'. The 24' length is the way I plan to put floor joists...I want the floor to handle 20k pounds. I am planning to put double 11-1/4" x 2" LAMS paired up at both ends and a pair 5' in from each end for a total of 8 LAMS. I will then joist hang dimensional 2x12s to complete the floor structure.

Can anyone confirm if this is sufficient structure?

 

[DIC]

20k pounds ??

 

[bazzateer]

Probably better to ask a structural engineer?

 

[jimp]

Go to an real lumber yard and they will have the engineered lumber supplier design your floor, mine did (no charge for the service and the codes people wanted to see the design and loading info.). 20,000 lb.s is ~50#/ft2, not unreasonable(assuming 20,000 lb.s is not a point load, but evenly spread out.)

 

[CNGsaves]

Pictures ??

Country ??

What you plan on putting up there to total 20K lbs . . and . . . how you going to get all that weight up there?? Big honking forklift ?? Will this entail multiple vehicles ??

Inquiring minds want to know !!

 

[mark5767]

I helped my dad build a mezzanine in his metal pole shed years ago. It was prolly something like 16' x 24'. It was pretty heavy duty and he stored a lot of car parts up there so it was quite a load.

Anyway, they had a severe wind storm that knocked over some pole sheds in the area and his was damaged to the point where it eventually needed to be taken down, but it didn't fall over and to the untrained eye actually looked ok. What kept it standing? The mezzanine!

By the way, I accidentally dropped a floor joist on his head while we were building it... should have killed him but he was too tough to die! Whole 'nother story tho... good luck with the project!

 

[cburnscrx]

We did this years ago at the factory I worked at...wish I could remember the plans we used. It was strong, and very stable...and we stored mechanical equipment and hardware up there.

 

[larry_g]

Pictures ??

Country ??

What you plan on putting up there to total 20K lbs . . and . . . how you going to get all that weight up there?? Big honking forklift ?? Will this entail multiple vehicles ??

Inquiring minds want to know !!

That is only 125-150 bales of hay.

lg
no neat sig line

 

[CNGsaves]

That is only 125-150 bales of hay.

More like twice that . . . . AND . . . would have to be alfalfa at 80 lbs a bale (ie the small square ones) - - - say 250 bales at 80 lbs = 20K lbs. Prairie grass would be heavy, but not as much as alfalfa. Straw bales weigh very little.

Never had seen any round bales (BIG ones) stored off the ground, and they are super damn heavy, and only a handful would fit up there, creating a great risk of damage if they fell.

* * * * * * *
Hadn't thought of pure ag use however. OP will have to tell us what plans for mezzanine really will be.

 

[sandslot]

Go to an real lumber yard and they will have the engineered lumber supplier design your floor, mine did (no charge for the service and the codes people wanted to see the design and loading info.). 20,000 lb.s is ~50#/ft2, not unreasonable(assuming 20,000 lb.s is not a point load, but evenly spread out.)

Thanks for all your comments....Yes I was talking about 20,000 pounds generally spread out....sandblaster, parts washer, press, tools, parts, etc. I plan to build a trolley like system with a bucket to get things up there....

Jimp, Is there a lumber yard you recommend I call that could help?

 

[Buzzards]

Thats a big floor and span. Do you plan on any centre beams? Standard floor construction should give you about 45 lbs per sq ft. You wood be maxed out with your proposed weight. To clear span that space you will probably need to use 14 - 16" joist and maybe 12" o/c.
We built a barn and clear spaned 30 ' for a mezzanine and used a open web 24" floor joist at 19.2" o/c. However you won't need that.
If you can lay your joist the 20' span that will help for size of joist and cost. Sounds like to me you need to use a plywood floor joist [TJI] on the whole floor. Your local lunber yard will design, engineer and supply the proper floor for you .Good luck buzzard

 

[jimp]

I have used Mc Cray for a complete floor and CMI for beam sizing, Both sent it out to the supplier (CMI sent me to the supplier to get the drawings).

 

[brownbagg]

20,000 pounds, that is red iron, and concrete decking. thats a fully loaded concrete truck. that is seven toyota pickup trucks

 

[larry_g]

20,000 pounds, ...Snip...." thats a fully loaded concrete truck.

You must have tiny cement trucks in your area, as cng has tiny bales of hay.

lg
no neat sig line

 

[Justanoldguy]

google says ............

A typical fully loaded concrete delivery truck can weigh up to 70,000 pounds (35 tons). An empty truck weighs between 20,000 and 30,000 pounds and a full load of 10 cubic yards of concrete weighs about 40,000 pounds.

 

[sandslot]

You're right....I talked with Weyerhaeuser and they told me to use 14" TJIs on 16" spacing, but I'll do 12" spacing for added structure....should be good for 30000...will let you know how it goes

 

[AndyA]

40 lbs per square foot is typical design for residential floors.
40 * 20 * 24 = 19200 lbs.
I'd say the 20,000lbs number is spot-on for residential, maybe even too small for heavy storage.

 

[sandslot]

I landed on an 85#/sqft for the design. I hate flimsy/bouncy floors. The technical folks at Weyerhauser were fantastic - answered all my questions.....and I had a bunch! I arrived at Weyerhauser TJI560 14" I-joists at 16" spacing. To accomodate my small 1500# hoist (to be placed in the center of the room), I will be supplementing the design with two 14" LAMs that I will epoxy and bolt in the I-joist bay. I'll send some pictures along the way. Buzzards, this turned out similar to what you suggested

 

[soapii]

20,000 pounds, thats a fully loaded concrete truck.

Huh? More like triple that.

A concrete truck hauls 9-10 cubic yards of concrete. 1 cubic yard of concrete is about 3000+ lbs.........that is 30K pounds of just concrete. The truck is another 30K pounds by itself.

--Joe

 

[Southernbuild]

You must have tiny cement trucks in your area, as cng has tiny bales of hay.

lg
no neat sig line