Concrete Question

[Jeff May]

I'm getting ready to move my air compressor to the outside of my shop.
I'm going to pour a 3' x 8' concrete slab to build upon.
Looking for opinions on thickness and whether I should use bags of Sakcrete or get some gravel, sand and portland cement and mix my own.
I'm guessing as large as what this slab is it may be beneficial to rent a small mixer instead of a hoe and wheelbarrow.
So,
Any suggestions or things I should be aware of for putting my air compressor outside?
Thanks,
Jeff in Hagerstown

 

[Bondo]

Ayuh,.... I'd go atleast 4" thick, 'n use a mixer,...

Whether ya buy bag mix, or mix yer own, don't really matter,...

 

[dlcwent]

Jeff.. what kind of structure are you planning to build on it?

 

[METALMOVER]

Id probably call a local concrete plant, they have little trailers you can pick up with up to 3 yards of concrete, give them your measurements and theyll give you the amount you need. Youll need a minimum of 4in. thick. Goodluck METALMOVER

 

[Angelfire]

Go 4" thick. A rough calculation shows you need just over 8CF of concrete to fill that area. Last I remember, the bags contain .67cf per bag so you'd be looking at mixing just over 12 bags....not all that hard to be honest.

 

[theoldwizard1]

Just to expand on this ...

How big of an area (assuming a 4" slab) would be reasonable for one man to mix (in a mixer) and pour by himself ? How about 2 men ?

 

[Leaflessshadetree]

I'd get the sand, gravel and cement and mix my own. I usually add cement to the Sakcrete anyway.

 

[volleyball]

May be cheaper to get a quieter compressor and put some sound deadener around it.

If you need the space, I would build a larger shed and fill it with other stuff than just a compressor.

 

[David C]

I can't imagine why you would want to use less than 4" of concrete.

Depending upon the size of the compressor, ie it's weight and the vibration induced during operation, I would use even a thicker slab. I don't believe there are any concrete anchors that work in less than 4" and most of them require a greater (than 4") EMB depth. Again depending upon the compressor size you would use the undercut concrete post installed anchors.

Use reinforcing too.

 

[cdestuck]

Did a couple pads and only used a mixer for the first and it was more of a pain than a wheelbarrow and hoe. So that's what I used. ****, two summers ago I did a 9 x 17' pad with bags and a hoe. Two days and a good workout.

 

[theoldwizard1]

Did a couple pads and only used a mixer for the first and it was more of a pain than a wheelbarrow and hoe. So that's what I used. ****, two summers ago I did a 9 x 17' pad with bags and a hoe. Two days and a good workout.

I'm impressed !

That is about 85 - 80lb bags of concrete mix. That is over 3 tons dry !

 

[blazentrout]

Just to expand on this ...

How big of an area (assuming a 4" slab) would be reasonable for one man to mix (in a mixer) and pour by himself ? How about 2 men ?

depending on air temp and sun/shade
1 man=64sqft
2 men=200sqft

Myself- age 37 at the time a 6'x8'x4" slab in a 4'deep hole for a crawlspace floor using a wheelbarrow(2 60lbs bags per mix). not bad, upper body workout for sure. floating it sucked. Time wise iirc was just over an hour and half.

Myself and my dad-(37 and 57)did a 6'x20'x4" on grade slab by the wheel barrow and that is about the max i would want to do by hand in one shot. it was nice having someone to run the water and help with running the wheel barrow and finishing.

What i learned is the bag comes off the truck right into the wheel barrow. back the truck(trailer) as close to mix point as possible and keep the push distance to a minimum.

 

[GTO]

Just get 14 80# bags of gravel mix,add water and be done with it.
That's enough for a 4" slab,put some rebar in there too.
You're making it more difficult than it has to be.
Good luck

 

[nolimits76]

8' x 3' x 4" = 8 cubic feet or 0.30 cubic yards of concrete

I'd call nearby concrete plants and advise them what you need and ask them if they have any jobs going on X day in the area that you could buy from them. That is basically "scrap quantity" to them. Chances are you will get it dirt cheap and have a better mix.