Elevated Concrete Slab Garage?

[DanHoug]

so i gotta ask... what is beneath it on the first floor? occupied living area? another garage? are there penetrations from second floor to first (think fuel tank leak)? what is the egress from that first floor?

unless there are absolutely no alternatives for a garage, i'd consider turning it into a workshop or other space. structually, i would think it would be fine, it's spillage of fuel that would concern me. depending upon design, that first floor may be a confined space and create a truly explosive environment.
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-dan
60% of what you find on the internet is wrong, including this post.

'87 Westy & '89 Westy both 2.1 4spd

Past projects can be found at--
www.thefixitworkshop.com

[Sodo]

Was waiting for pics first,,,,,
Dunno if this is appropriate to the situation.
Not ideal if the local building inspector rents the apartment below.

================

OK here's a cowboy approach.
Load-test it to 11,500 lbs?
Rent this.

You will need a truck that can tow 12,000 lbs. A 2500-series or F250 etc can tow 12,000 lbs.
Rent a dump trailer like the one shown. ($200 for 4 hours?)
Buy 3 yards of gravel (2835 lbs/yd * 3 = 8500 lbs) cost appx $35 per yard?

Total weight (with trailer weight 3,000 lbs) is 11,500 lbs.
This is more than twice the weight of a Vanagon.

Put the truck in 4WD low, set the locker, and back that sucker onto your garage slab.
....ready to rocket outta there if your capable assistant reports any signs that the slab can't hold it.
Leave it hanging there as long as you are comfortable.

If you have a need for 3 yds of gravel onsite (or know someone who does) this method becomes fairly economical. Especially if you can borrow a truck or trailer.

Park Vanagon on slab.
Spend $$ on something you need.
Sleep well.
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'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb

[jimf909]

Bonus: if it doesn't hold insurance will cover the damages.
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- Jim

[jackbombay]

[space]

I have an "elevated" concrete garage floor
Flexicore was used
it was engineered to hold the weight of 15k lbs (3 car garage)
I do like the Pool method for a test

[Sodo]

If you have a use for 6 yds of gravel could do 3 incremental tests, 1+2+3yds

For the pool method:
Water: 10,000 lb / 8.1 lb/gal = 1234.56789 (!) gallons
Water: 10,000 lb / 62.4 lb/cu ft = 160 cu ft = 8’ x 10’ x 2’ deep
or appx 10’ diameter x 2ft deep

Or get 50 200lb humans.
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'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb

[rmcd]

Oh yea. Kiddy pool test is best. Failure will be spectacular and all the evidence will wash away. Pull the pool plastic away and tell them you don’t know what happened. I’m laughing so hard I should be indited!
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VW LT40 build. Like a Vanagon but 30% larger in every direction and 40% slower even in metric.
https://www.thesamba.com/vw/forum/viewtopic.php?t=749359&highlight=

[dobryan]

So OP do you feel lucky? Do you punk?

All kidding aside the test until failure comments are valid but BS in a world where you need a permit. What world are you in?

And what do you do if you do those tests and drop that slab into the basement?
(Folks this is not the same as saying change your fuel lines to a
new bus owner.)
_________________
Dave O
'87 Westy w/ 2002 Subaru EJ25 and Peloquin TBD

"To travel hopefully is a better thing than to arrive." Robert Louis Stevenson

MD>Canada>AK>WA>OR>CA>AZ>UT>WY>SD
https://www.thesamba.com/vw/forum/viewtopic.php?t=620646

Building a bus for travel in Europe (euroBus)
https://www.thesamba.com/vw/forum/viewtopic.php?t=695371

The Western Syncro build
https://www.thesamba.com/vw/forum/viewtopic.php?t=746794

[DuncanS]

Wait a minute. I assumed that there was a no access crawl space under the slab. A couple of possibilities. With a water lever--hose--you can check the thickness of the slab. That doesn't mean it is reinforced, but a start. Then if you can get underneath, why not just add a bunch of columns under where the wheels will go combined with a beam to distribute the load. 2x's will do just fine. Any pasted together 2x8, 10, or 12's should be oriented vertically. Wedges hammered in at the bottom where there needs to be a pad should take care of it just fine. If the columns height is over 4', I would double the 2x4 posts. Assuming the space under the slab is not currently important or useful.

[AZ Landshaper]

Whats underneath? Did I miss that part?
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85 Weekender w/ EJ22
Previously
64, 71, 72, 73, 76, 81, 84, 85 & 87 Campmobiles and Westfalias
and a 67 bug.

[Gauche1968]

Still waiting to get some pics. There is an unfinished, low ceiling, storage, workshop area underneath the elevated slab. It is not living space. The upper level of the garage is at grade with the alley behind the house, the lower level at grade with the back yard. So, it looks like the lower level of the structure is also acting as a retaining wall on the slope.
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1984 Vanagon GL
1984 Vanagon Westy

[Abscate]

[Sodo]

[DuncanS]

Post beams and lally columns. Just do it, you will be fine. Don't even bother with the 1/16" gap. Since you will have the posts underneath anyway to carry any deflection, there will be no flexing stress put on the slab by having them tight against the underside.

[Sodo]

The “1/16 gap” is only for adding posts for the proof testing only. Its purpose is to indicate deflection due to “the test weight”. And the post becomes a safety limiter during the test, for the case where the 1/16” gap closes up. If there’s no deflection, theres no post required (in that location). Test weight of 2x vanagon 8,000 lbs? 10k? is probably sufficient to make a good decision.

For the “permanent” columns, fireproof posts might be a prudent choice. 6x6 (oversized) wood is not fireproof per se.... oversized wood often used simply because the un-burnt core retains its compressive strength for a longer period (provides more time for the fire truck to arrive). Steel becomes a noodle when red-hot, so it has to be protected from fire, (usually by concrete).
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'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb

[Zeitgeist 13]

Is this the Ferrari "shed" from Ferris Beuler's Day Off?
_________________
Casey--

'89 Bluestar ALH w/12mm Waldo pump, PP764 and GT2052
'01 Weekender --> full camper
y u rune klassik?

[Tully Mars]

As someone who has renovated 4 old warehouse buildings into Lofts.. I have some experience with this.
You can have the slabs Xrayed to show the layout and size of the rebar... if any.. Should be some. The earlier concrete structure buildings were built around 1920. But it was several years before they came up with deformed rebar like we use today. The early bars were smooth and did not have great mechanical connection with the concrete.
You can have core drills done of the concrete and have them tested for compressive strength. Put this together with the details on the "I-beams" a structural engineer can calculate the load capacity.
It will not be cheap to have this done..

This building was load bearing exterior walls but interior was concrete columns and slabs.. cast in place.
https://drive.google.com/file/d/0Bz8swHo5FQuFMjF4TjBsWTI2QWM/view
_________________
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If I have to.
I guess.
_______
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[Gauche1968]

[my59]

You want to do what is termed NDT, non distructive testing. Your engineer should know someone who can come xray or use ground penetrating radar to find the reinforcement pattern

Is this a single bay, or is it a 2 car garage?
Is the distance between the columns similar to the distance from the colum line to the side walls?

The issue with parking on it is the tires provide concentrated load points, and I have seen crap parking garages with holes blown in the deteriorating slab from cars parked. The slab reinforcing mesh rusts, expands, causing cracks in slab and so the slab is no longer cohesive. Weight of car 'punches' a hole in the slab.

The pool idea is great, but it is putting a static uniform load on the slab, not a moving load like a vehicle. I'd be concerned about having a safety factor, and unintended "test to failure".

Of course, you could just say screw it, and pull into your garage, because it was built to be one.
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Other:'12 Jetta, '77 Benz 300D, and a 74 MG Midget.

[nsracing]

Post pictures of the garage so we can see it.

I own a two-level garage/building built in the 1920's. The lower level is below grade so I have a garage door in the upper and lower. The upper floor is 10 inches set on its 50-foot span w/ 30" huge steel beams and concrete w/ column in the middle. The building was a machine/steel shop in the upper and lower.

The foundation is poured concrete and concrete columns support the edges of the beams. It is built like a bridge on its upper floor. The building has bricks all around. This garage is my pride and joy. It even has a deep well inside and sewer, 3-phase line, gas line.

It was grain storage too back in the day when they stopped building Model T Fords in it. The inspector said it is a nice building. It will be there long after I am gone.