Weight capacity for garage floor

[JimNC]

It’s a residential garage floor in NC. Will need to drill it to check thickness, but assume 3”.

I am planning to install a pallet rack against the back wall to store some metal. Total weight will be about 6,000-8,000 lbs. Four posts, each 3”x3”.

I’m anxious to get this project going, but a little concerned about cracking the garage floor.

Is it a non-issue?

Thanks
Jim

 

[ddawg16]

You will have about 220 lbs/sq in

Put the posts on a 6x6 1/4" steel plate and you drop the load to about 55 lbs/sq in...about par to a typical large vehicle.


But, we don't know the PSI of your concrete, if there is any rebar in it....or what your foundation looks like.

But if your garage will support a heavy truck....you should be fine.

 

[matt_i]

I wouldn't sweat it. The 220 psi is 1/10 of a really bad concrete at 2000 psi...most are 3000-4000psi

There's the unknown issue of the subgrade condition, but there's really only one way to find out.

The idea to use metal plates at the foot is a good one, but I'd go with aluminum or hardwood as those are unlikely to corrode and leave a rusty spot on the floor that would be tricky to remove later, should this system change in the future.

 

[JimNC]

Thanks guys, I’ll need to shim the system to level anyway, so a piece of hardwood on the floor with 6x6 steel shims on top seems like good insurance.

Jim

 

[sberry]

I have steel racks.

 

[lonestarky]

Like everyone said, a large truck like a big modern pickup can be close to 8000 lbs (3/4 ton diesel).

You will be fine.

If overhead clearance is an issue, and hardwood shims won't work, you could get a gallon of floor epoxy too, and just epoxy coat the spots where the feet will touch to prevent rust.

Sent from my Pixel XL using Tapatalk

 

[RVDan]

A large Diesel engine on an engine stand well exceeds that load. My garage floor didn't collapse.

 

[4cyclic]

Put a couple of coats of rust primer under the steel pads, problem solved.

 

[wssix99]

You will have about 220 lbs/sq in

Put the posts on a 6x6 1/4" steel plate and you drop the load to about 55 lbs/sq in...about par to a typical large vehicle.

No need for plates. If the slab is 3" deep, then the loads will spread out to a 9"X9" area at the base of the slab. That's 25 psi, which should be no problem as long as the base under the slab is fine.

I’m anxious to get this project going, but a little concerned about cracking the garage floor.

At 3000+ psi of strength, un-reinforced concrete is going to be fine; even if it's a thin slab. (You may check with your rack manufacturer to see if they have requirements for anchors and slab thickness.) Your limiting factor is going to be the strength of the base under your slab. The only thing to be worried about would be settlement under the slab around the foundation, which happens sometimes. When you drill your post anchor bolts, you can go all the way through and make sure you are on solid base. If not, you can have a company come in and grout underneath to fill the void.

 

[red61cj5]

My floors are 4 inch, 3000 psi if I remember correctly, and I drove my 8 ton backhoe over the threshold and into the garage. Not a crack,though I was a little worried about the edge.