[jlaky2000]

I live in the Chicago area and am planning to construct a shed this spring (one of those assemble-yourself wood ones -- 8' x 12'). I want to put it in the back corner of the yard, which is shaded and unused. The problem is that grading of my yard (and the neighborhood, it seems) is such that this corner also gets pretty wet, particularly in the springtime (silty-loam soil with shallow water table near Lake Michigan).

My question to the forum is: Should I have someone pour a concrete slab for the shed, or should I build a low deck off the ground and build on top of that?

Also, is frost heave a concern for the base of such a small structure?

 

[joecaption]

Can a truck get anywhere near that area to deliver the concrete? If not go to plan B.
If you went with a slab you would need to dig out any top soil and back fill that whole area to get it above the grade.

 

[jlaky2000]

Thanks, Joe. No a concrete truck could not get to the back yard, and it is a good 100' to the corner of the lot from the back of the house. I guess that I'll go with plan B (the low deck).

 

[funfool]

Just a thought, I watched some guys assemble a pre-built tough shed.
What they used for the framing of the deck was metal studs.
I am not familiar with the different thickness of these studs, other then interior studs are flimsy, exterior wall studs are thicker, And imagine they have some even thicker yet.

Anyways they leveled it out on concrete blocks and added a 3/4" sub floor deck to it.
Is very sturdy, galvanized metal so no rot, may cost a couple dollars more, next time I build a shed on a deck.
I will use the metal studs. Just a thought as a alternative to using wood framing close to the ground.

 

[AllanJ]

I do not think a concrete slab is inherently superior to a raised deck.

Concrete is porous and the underside of the shed structure is subject to moisture. This will affect metal framing (causing rusting) as well as wood.

 

[joecaption]

If it was mine I would use 6X6's as post and build the floor just like a deck is built.
Do not try and cheap out and use undersized floor joist, use at least 2 X 8's 16" on center. Install then with joist hangers.
It would be far better to also add a center beam to stop any sagging or bounce.
The whole shed needs to be about 12" up off of grade to prevent mold and fungus from growing on the underside since it's so wet there, and to prevent splash back from rotting out the siding.
Just build a ramp in front of the door.

 

[dengle]

The other point to consider is a concrete slab may raise your taxes as it's a permanent structure/addition.

I assembled one of those plastic 8' x 10' sheds at a previous house. For the base, I first framed out the area plus a little extra(I gave myself a good foot in all directions) with 4x4 pressure treated, trenching/leveling where needed so that the entire framing was level. The area I was using was pretty sloped so I needed two courses of 4x4 to manage just a few inches above grade in the one corner and had the full 8 inches on the other corner.

I then filled the "box" with blue stone to allow for drainage. It also served as a level base and a dry area to stand in front of (depending on how big you make it) when entering the shed.

After that, I built an 8'ish x 10'ish wood frame again with PT 2x4"s with a 3/4" exterior plywood top that was painted with exterior paint on both sides just to give it a little extra protection. The whole thing was inexpensive and built in a day. Water was a non-issue as the crushed stone allowed the water to drain easily.

I filled the pockets again with blue stone to help keep critters from making nest underneath as well (also i order too much so had to put it somewhere! ).

Just saw this, which may work too. The "shed feet" is an interesting idea. Never saw those before:
http://www.secrets-of-shed-building.com/shed-base.html

 

[747]

I had a concrete slab poured for my tool shed. If you can't get to it. Its the way to go. You can then drill into concrete and tap anchors for the lags to bolt into. This is what i did.