Adding height to a 4 post lift?

[sierradmax]

I would like to purchase a 4 post lift to store a corvette for the winter. The best location is in one bay of the attached garage. This has 13'-6" ceilings but it's typically where I park my truck that has an overall height of 7'-3".

Most "extra-tall" 4 post lifts have an overall drive-under of 6'-8" with the exception of a couple "super-tall" but their column dimensions exceed my ceiling height.

Has anyone added height by installing their lift on elevated concrete piers, 2by's,r etc. then dealing with either longer ramps for the increase in platform elevation when lowered? In my case, I would probably need 8" in extra height if I opt for an "extra-tall" 4 post lift.

 

[ChaseDE]

I would think it is doable, you would want a structural engineer to do some calcs on it though. You could end up with some very wide and/or deep footer requirements.....maybe.

 

[GMCGarage]

If its a 4 post lift, some concrete pedestals would work. Its not going to add that much more weight than the original lift on your slab. Dowel it into the slab with epoxy.

 

[sierradmax]

Weight shouldn't be an issue at all. You are only adding a couple hundred pounds to each column of the lift from what it is right now, so if the existing concrete floor isn't cracking from the 4-post lift columns you shouldn't need to do anything special to handle the load.

Your plan sounds totally doable to me. I would be thinking along the lines of drilling 4 holes in your existing concrete pad for each column (make the holes line up with the holes in your column base plate). Then epoxy some long threaded rods down into the holes you drilled, and make sure they will extend higher than the raised pad height after the concrete pad is finished. Set a cardboard sonotube in place around the threaded rods and cut it to the right height for the amount of lift you want. Thread a nut down each threaded rod until the high side of the nut rests flush with the top edge of the sonotube. Fill the sonotube with concrete, smooth the top, and let it dry. Use the protruding threaded rods to bolt the lift column to the top of the raised pad and you are good to go. Having a nut embedded in the concrete underneath the column base plate, and another one on top of the lift column base plate will ensure that everything stays in place even if the concrete platform crumbles and falls out from under the lift column in the future. I would size the sonotubes so they are around 1-2" larger in diameter than the diagonal measurement of the lift column's base plate. If you use good quality high psi concrete for the lift platforms and mix it thoroughly you should be just fine.

Although this sounds like a great idea, is something this excessive really needed? The 4 post I'm looking at is the Atlas Garage Pro 8000 Extra wide, Extra Tall. The installation instructions mention that the lift columns do not need to be anchored to the floor. Each column has a 9-5/8" x 11-1/2" baseplate.

My idea is to through-bolt, lag, etc. size pieces of PT 2x12 cut to 13-1/2" creating a 9" "baseplate pedestal" for each column then lagging the baseplate to the PT lumber.

 

[cvairwerks]

I would spend some time on the phone with the lift guys first. They may say no way due to design issues that you are not aware of. Installing it on raised piers brings in some major engineering changes that have to be dealt with. The normal installation makes the assumption that the top of the pier is going to be restrained by the slab. By elevating the top, you have now removed that constraint. Any movement of the lift is now going to be magnified. This in turn changes the mounting bolt/ j bolt loads. Is there enough safety margin the original specs to handle the change? I don't know, and unless you are a structural engineer, you can't eyeball it or guess if there is or is not.

Elect to elevate it on piers, then spend the dollars for a set of stamped drawings, based on your local conditions before you actually do it. I will bet that what the engineer comes up with is considerably larger and has more to it than you think.

 

[SuperCheyenne]

Most "extra-tall" 4 post lifts have an overall drive-under of 6'-8" with the exception of a couple "super-tall" but their column dimensions exceed my ceiling height.

I'd call the lift company and ask how much for a custom height... or I'd trim it down myself (I have access to a manufacturing facility so this may not be doable in your case).

 

[Kev442]

FWIW, I had my 4 post on solid concrete blocks for several years prior to pouring concrete. I believe one corner was shallower than the rest and was on pressure treated lumber. The car I stored on it weighed less than 3000 lbs.

 

[mbshop]

The taller you go, you will run into stability risks even with a 4 poster. Even on a level floor I would bolt it down. Lets be safe.

 

[lakeroadster]

I'd fabricate some steel tubing "cans" that weld to the lift base plate perimeter, that are secured to the concrete with (4) 3/4" diameter epoxied anchors, each can.

Securing the cans / lift to the floor will be a must.

Cans would simply be square or rectangular tubing ( heavier gauge and dimensionally equal to or larger than the columns ) with 1/2" plates welded top and bottom.

Might be prudent to use 4 jack stands on the runway to slab when loading.

Keep in mind your drive thru width for the truck will be reduced slightly since the base plates will be up in the air, not on the slab.

 

[doogdoog]

I would have a machine shop or yourself if you are capable to make an identical base plate as the lift and another one possibly a little larger to act as the new base plate and bolt them together. Use a rectangular or square tubing that can handle the stress to fit between and weld to the new plates. First, submit your plan to a structural engineer to see if that would work.

 

[cvairwerks]

Jeremy: Think back as a kid trying to balance on a coke can without crushing it. As long as all the force was perpendicular to the floor and parallel to the can side, it wouldn't fail. The instant you got the forces out of alignment, the can buckled and squashed. Same forces and principles are in play if you mount a lift on columns. For stability, the "cans" ( read that as columns ) need to be designed for those loads. Otherwise, as little as a hard stop could provide enough movement in the lift, that it causes a column failure due to the buckling loads. A structures guy should be able to design the columns with all that taken in to account and then maintain the manufacturer's safety margins. Wouldn't want a moment's goof to topple a loaded lift.

 

[PoorOwner]

No one thought about how a corvette is going to drive up onto a runway now 10" high? You are going to need some 6 foot long ramps at the minimum.

Can you rotate the lift 90 degrees with the corvette on the lift with casters on and back the truck in. Problem solved.

 

[lakeroadster]

No one thought about how a corvette is going to drive up onto a runway now 10" high? You are going to need some 6 foot long ramps at the minimum.......

The OP mentioned that in his 1st post...

Has anyone added height by installing their lift on elevated concrete piers, 2by's,r etc. then dealing with either longer ramps for the increase in platform elevation when lowered? In my case, I would probably need 8" in extra height if I opt for an "extra-tall" 4 post lift.

 

[ddawg16]

How about lowering the floor under the lift?

Then you don't have to worry about ramps

 

[sierradmax]

No one thought about how a corvette is going to drive up onto a runway now 10" high? You are going to need some 6 foot long ramps at the minimum.

Can you rotate the lift 90 degrees with the corvette on the lift with casters on and back the truck in. Problem solved.

Yes, I'm sure I will have to fabricate some longer ramps.

 

[sierradmax]

Has anyone heard of TCE lifts? I found this at Northerntool.

http://www.northerntool.com/shop/tools/product_200621702_200621702

it has a 87-1/2" rise but claims a compressor is required.

 

[rsanter]

How about lowering the truck?

Bob

 

[sierradmax]

I've never heard of TCE. The compressor is usually used just to release the locks, so even a small pancake compressor would work. Several other popular lifts operate the same way.

The 87-1/2" rise spec sounds like they are telling you how high the deck will go, not how much clear space there will be underneath it at the highest position. It looks like the thickness spec for the deck is 5", so I think that lift would have a 82-1/2" clearance spec if no part of the deck is thicker than 5".

There was a response from a questions asked about the 87.5" and it was replied as "underneath clearance"

 

[sierradmax]

You are right... Good call. Their numbers don't seem to add up.
http://www.tcelifts.com/7-000-lb.-series.html

 

[sierradmax]

A quick question to Northern Tool and they replied back to me via email to defer to TCE. I called Atlas equipment and they recommended that I dowel threaded rods into the existing slab and form piers to gain elevation while the threaded rods continue to anchor the baseplate to the pier. They didn't have a warm and fuzzy feeling about answering how much of a reveal is needed on all 4 sides of the piers but recommended 6"! Not sure on how my approach will be but I'm certainly not lowering the truck.

 

[lakeroadster]

The dowels are due to the concrete piers inability to handle bending loads.

So you're not even considering the steel can idea?