To slab, or not to slab - concrete that is

[AIM]

Wow, that wouldn’t work ‘round here Aim , I’ve seen 12 inch thick slabs poured without footings for round corn cribs… and I’ve seen the frost heave an empty crib enough to topple it.

I doubt the frost toppled the crib. The soft surface under the crib compressed would be a more likely scenario. I have seen WAY more problems with things sinking than I have with things heaving. And I would NOT pour a corn crib without a footing. Were talkin SHEDS here.

 

[AIM]

Getting experienced help is great advice and if the budget allows by all means do so. I'm gonna guess that the help will cost you in the $6-800 range. If this isn't in the budget or you simply want to tackle this yourself don't be afraid. Prepping, pouring and finishing a concrete shed floor isn't to difficult. If you chose to do this yourself just ask the questions and many of us here can guide you along. Hell even Spidey might have some good input. (just pokin at ya Spidey)

 

[Fedaburger]

Usually jobs are priced by takiing the price of concrete and multiply that by two thats usually a ball park estimate.

 

[Steve2910]

Hell even Spidey might have some good input. (just pokin at ya Spidey)

I wasn't aware that there were ANY topics discussed here that he WASN'T an expert on, or DIDN'T have a strong opinion about.:hmm3grin2orange:

 

[cnice_37]

Getting experienced help is great advice and if the budget allows by all means do so. I'm gonna guess that the help will cost you in the $6-800 range. If this isn't in the budget or you simply want to tackle this yourself don't be afraid. Prepping, pouring and finishing a concrete shed floor isn't to difficult. If you chose to do this yourself just ask the questions and many of us here can guide you along. Hell even Spidey might have some good input. (just pokin at ya Spidey)

This is exactly what I was expecting as well. For some reason, my shoot from gut pricing instincts usually are spot on. I figured just under 4 yards, so would be a $700 job on the low side. Given more time (placed the order to get the "tax free" benefits tomorrow - saving me a whopping $100) I might have decided the concrete. One down side is we live about 1 mile from a quarry, and the blasting will crack surfaces... perhaps my tiny wimpy slab. Compound that with the height I needed on the lean-to, and I've had needed to gone to 10' walls. This of course made me think more about pole barn style, and I finally stopped chasing my tail and placed the damn order.

Usually jobs are priced by takiing the price of concrete and multiply that by two thats usually a ball park estimate.

Nice, so again, my estimates were good even though I have no idea what the hell I'm doing!

If it is a disaster, because you cut corners ,you will be looking at it for a long time

Yep, paint, wood, even metal aren't permanent... concrete kind of is. I couldn't afford to screw this up.

 

[loadthestove]

Does anyone know the three guarantee's of concrete????

I think I do..
1.- Its going to crack no matter how well its finished.

2.- Nobody can pour a concrete garage floor so water will run out the door (at least in my area) it will always pool next to the house when you wash the garage out.

3.- Always order at least 1/2 yard more than the dimensions call for that way lest you run out with a few feet left in the pour.

 

[D&B Mack]

So... what size slab would you recommend pouring (full length of course, 20'x'15') ? Thickness that is.
Is this a hire it out job considering I'm relatively clueless about this?
What might this run me? I can handle digging/ levelling/ tamping.
I'm in Mass, so we have frost heave... does this also require a proper footing? Yeah I know, ask the building inspector...

And finally, is it worth it?

-Craig

Yes, you can do it yourself. The hard part will be finishing it when you pour. You will need a few hard working hands to help you and the proper tools (which you can get at most rental yards). You will want more labor, if you are short and the concrete sets up too early on you, there is no turning back.

I tend to over-do things when they are for myself. So keep that in mind here. Prices are from around here.

1. You do not need a standard footer if your are not supporting any vertical structures on the concrete. You can put in column footers first and then pour a slab later. If you do this, you do not want to tie the slab into these footers. The column footers, assuming they are are installed to frost depth, will not move with freezing/thawing, but your slab will.

*I would, but not necessary, install a frost footer. Typically, this is down to frost line, 6-8" wide at the bottom. At most, one run of rebar. This will be poured monolithic with your slab.

2. I like clean aggregate for my subbase. You would only need 4" for a shed slab. I would install 6 if it were me though. Keeping moisture from standing below your slab is key to keep from uneven heaving. (7-8 tons, I would order extra as a backfill border around the shed rather than backfilling with topsoil straight up to your structure. $200)

3. I would install a 10mil vapor barrier. Some might not think it is needed in an unheated structure. But I like it cause it will help keeping moisture from forming on days of extreme temperature change. You are only building a shed, so just get some 10 mil plastic from a hardware store. ($200)

4. 4" concrete minimum. I like to use 4,000 psi concrete. This would take 4 cubic yards. You are going to pay a flat rate for the truck, then per yard for concrete. ($530). If you are going to install frost footer, just figure out your volume and add your per cy price since you will pour all at the same time anyway. You could use wire mesh to reinforce the slab if you are going to running a larger tractor in the shed. ($75) I like to use 5" thick concrete if I am using wire. ($600)

5. If possible, elevate the bottom of your slab so it is slightly above the surrounding grade. This just helps with keeping water from collecting under the slab.

Hope this helps, good luck.

 

[stihl023/5]

Also check your tax code for each option where I live a wood floor is not considered permanent poured is. And taxed of course higher.

 

[half]

concrete floor

If you are going to have a go yourself, get the boxing right, remember concrete weighs about double the same amount of water, hire the good gear to finish it with, get a good team to work with, have you got access for the truck?, If not, you need a heap of barrows, usually 20 barrows to a yard, to shift it. And nothing puts the panic in faster than a floor not finished thats going off. If you can get the truck as close to the floor as possible you may be able to :shute; the concrete to the end nearly, and just rake it to the sides

 

[Dale]

A shed doesnt really need concrete and a shed most certainly does not need a 24" by 12" footing of concrete. (overkill) just a tool shed not a three car two story garage.

29 replies and this is the best one I've seen. You are constructing a rudementary "lean to" type structure to mainly dry wood, with a slight wing to store a tractor. Most if not all of this will have open sides unless you like your wood wet for a long time. FOOTERS ???? for WHAT ??? You don't need no stinking footers. I've poured and worked concrete for 30 years. Driveways I prefer 6" thick to carry the oddity of having a large truck or heavy vehicle. You are simply stacking wood. Pour your pad 4" thick, anything else is serious overkill and a waste of money for your application. The bad will not heave or alter noticably at all. I'm in PA, and we get some tough winters. IF you are building a house, or a ful-fledge garage, of course you want footers. I prefer to pour monolithic.

Since you have no idea what you are doing, get at least 2 people to "work" and "finish" the concrete. A few more pals with no skill will always be a big help to perform the gruntwork. Remember: IT'S A WOODSHED... DONT OVERTHINK IT.

 

[hdpowers]

the thickness depends on what your going to put on it, 6" will handle anything you wanna put on it, only place id put a footing is the entrace, been pouring concrete 20+ years, use 3-4" of either 3/4 clean or ca-6 to get a hard base then order a 6 bag mix with fiber mesh in it, cut a joint every 10' concrete will do 3 things: get hard , turn gray, and crack,

 

[Woodomaker]

So I'm building a shed. I posted a few Q's in the OT forum but it's quiet over there unless you want to play silly games.

It will be made of wood. Maybe one day I'll burn it - there, it's firewood forum appropriate now.

The shed will be just under 300 sq ft (setback requirements) with a main shed at 12'x15' and a lean-to at 8'x15' for the tractor. Originally, this was going to have "2 wings" with another lean-to for a proper wood shed, but the size and setbacks make the woodshed a second building to happen ????

I have no experience with concrete aside from pouring a sonotube here and there. My plans were for no slab, 2x10 floor 16" oc for the main shed, and an earth floor for the lean-to (possibly followed up by a paver floor seeing as though I've got over 100 of those lying around.) I've priced it out, and think the flooring/ lumber alone and I'm at $600 (all PT.) That's no blocks, skids yet either so even more.

So... what size slab would you recommend pouring (full length of course, 20'x'15') ? Thickness that is.
Is this a hire it out job considering I'm relatively clueless about this?
What might this run me? I can handle digging/ levelling/ tamping.
I'm in Mass, so we have frost heave... does this also require a proper footing? Yeah I know, ask the building inspector...

And finally, is it worth it?

Thanks a lot for any insight.

-Craig

Concrete might add to your tax bill too......