Floor thickness for 2 post lift.

[birdman1]

Hope to pour a floor soon for a 30x40 shop. Want to pour for 2 post lift and the link for Panther Lifts stated a min. of 4" reinforced but I want to be sure about this thickness. A dually is about the heavest thing I can amagine I would have on a lift, like a F350. One contractor said I should dig two trenches about 6" deep and pour the rest at 4" reinforced. Should I pour 2 thick pads where the lift would mount? What are your views on brands of lifts? My son just heard of Panther, that's why I started there.
Thanks for any help
Mike

 

[nate379]

IMO a garage that is used as a shop should have at least a 6" slab.

 

[HoosierBuddy]

My 10000 pound lift specified a minimum of 4" concrete.

I was installing 2" of polystyrene under my slab with pex tubing for the heat. I took out the polystyrene for about 4' X 4' under where I was mounting the lift so those areas ended up being 6" rather than 4". It's been in for 3 years with no problems. I lifted a tahoe with it one time. Mostly mustangs though.

Phil

 

[birdman1]

thanks guys, good information---I hope to heat part of it with a through the wall "hog house" LP gas heater,or the 7 brick heater I already have,but the 7 brick will have the flame inside the shop and the wall job has the combustion on the outside,which will be safer
thanks, Mike

 

[pattenp]

My 2 post lift required a min of 4” reinforced. If the slab didn’t meet the required minimum then the lift manufacturer said to cut out a section about 4’ x 13’ and dig down to put in a 12” thick pad and key it into the original slab.

 

[kvom]

My slab is 4", with 2 6" pads for the lift. There is no rebar in the pads.

 

[brownbagg]

If was pouring a new slab, I would go at least 12 inches where the lift was and would think about anchor bolt, just because a yard extra in concrete is cheap. Mine is only five inches but to be on the safe side

 

[checkthisout]

I am probably the only person on this board who has witnessed 3 lifts pulling out of the ground.

More accurately, the lifts breaking the concrete.

I was teching at a very LARGE ford dealership and 3 different hoists pulled out of 4" inch concrete over the years.

All were ASSYMETRICAL hoists and all had E-VANS on them that were loaded to the gills with electrical and tiling supplies. I am guessing these rigs were almost 12,000 lbs with all the **** they had in them.

The failures happened very slowly and very undramatically and the concrete was fairly old and brittle.

A homeowner will never be in a situation or load/overload a lift like that so just follow the manufacturers reccomendations. If you are going to be servicing crew-cab Superduties and Extended E-vans then pour a 6 inch slab thoughout your entire shop.

 

[Notch1988]

I went 6" with rebar throughout. It's peace of mind the first time you lift your truck and have to walk under it.

 

[Shocker]

+1 on the 6".

 

[gsport]

some where on here there's a u-tube video of a two post that pulled out of the concrete with just a van on it, it did't say how think the concrete was.... but for sure i'd go thinker than required..

 

[birdman1]

Thanks guys, a few bucks now can prevent a bad accident and a healthy expense later. Can't imagine what if would cost to cut out the concrete and do it right later. If you do it right the first time you only have to buy it once!
Thanks a bunch, Mike

 

[Cryptic1911]

I went with 6" of 3500psi + fibermesh and chickenwire.. don't want that **** falling on my head when I get it

 

[janaka]

my builder did me a HUGE favour and put 36" sonotubes in for me during the pouring process. I now have 5' deep (yes 5 feet) 36" round pads for my hoist to be installed on. There is no kill like overkill.

i've read 6" is the recommended for 2 post hoists rated to 9k pounds or so.

 

[JMURiz]

I believe the bigger issue is how the bolts are attached to the floor, not the thickness. 4" should be fine, however more won't hurt. The bolts will move sideways when weight is put on the lift right, not straight into the slab?

 

[Motley]

4" is fine for a two post. More doesn't hurt, but less can. Lifts typically come with a 5 3/4" wedge anchor. By the time you subtract the thickness of the nut, washer and baseplate of the lift you are only going to have about 4" in the concrete. With those type wedge anchors, if the hole is drilled properly, they are not coming back up unless the concrete is weak. I have seen lifts come down and rip up huge sections of concrete, but the lift was still bolted to them. After 20 years of installing, I wouldn't have been able to install most of them if a 4" slab wasn't good enough. And as far as know, they are all still standing.

 

[birdman1]

thanks for all the infor. I had heard that the bolts go through the floor like a toggle bolt or something. I don't think that was correct information though.
Thanks, Mike

 

[Garys Garage]

My shop is 15 years old and has 4 in in most. I have heated floors and rebar. I lifted a 4 door duramax on it the other day. I had no problems but did not feel good about it. I poured a slap for my next lift , a 10,000, I poured 6 inches to be safe.

 

[Possum]

The manual for my two post 9000 lber states 4" of 3500 psi.

 

[birdman1]

Thanks again for the info. it helps to hear from folks with experience at these things.
Mike

 

[jimmie jam]

i just added a 600sf addition to my garage with 13' ceilings. the slab was poured 6" thick with 4,000psi AND there is wire mesh and #5 rebar @ 4' on centers. hope that will support my lifts.