Concrete blocks for a shed foundation in Michigan?

I've wanted to build a garden she for the last 15 years to get all the non car related crap out of the garage. It's always been rejected by the family CFO AKA Spousal unit as a)not needed, b)too expensive and c)an eye sore. Well now we have a rental house with an awesome shed and my wife can finally see the use and we also have a pop up camper that we want to get under cover. So after 15 years of NO, she suddenly has a bright idea 'Why don't you build a garden shed' Damn, I wish I was as smart as she is, I wonder why I never thought of that!!

Obviously I'm not going to start until spring. Michigan in November is not my idea of ideal out door project weather. But I'm planning and sketching a modern shed. The thing is the foundation. I'd always imagined doing a concrete slab. I poured one myself about 10 years ago for our hot tub and it hasn't moved a mm. The thing is I now have this mad cap idea of possibly extending the garage back another 20' to make it an L shaped three car garage and decent mud/laundry room behind the house, but that would be another 5-10 years out. If I'm going to do that I don't want a permanent shed and solid concrete slab to have to be moved (Sheds have to go behind the building so as not to be too visible from the street) Also I imagine being able to move the 'current' shed further back if/when the extension happens.

So what to do about a foundation for the shed? I see these Concrete block

and wonder if they work in colder climates where you have a strong freeze/thaw cycle. Even with my deck I buried the pilings 2+' below ground in concrete. Do these things work or does your shed walk around the yard like a drunk on the deck of a ship when the ground expands and contracts? What foundation do you need beneath them?

Thanks

We used them for our shed at our cabin (Northern Wisconsin, almost to the UP). We had to level the area a bit so I don't think they could walk away if they wanted too. It's been there for 3-4 years now, at least, and I don't see any issues.

I don't recall anything below the blocks, just a few inches top soil on top of feet of sand.

It's a garden shed. Doesn't need a foundation. Just build your base out of pressure treated 2x and the floor out of PT plywood. Find the flattest spot to build it, the load will spread over the entire ground area and sinkage should be minimal. Habitat for windows and doors, Home Depot for some cull lumber and you're away to the races. I built two 10x12 sheds on my lot in London Ontario years ago and they're still standing.

I built a deck on those type of blocks and it was still level when we sold the house. I've seen sheds locally that are built on a perimeter base of railroad ties. Darn near anything that's rot resistant will work.

I like the idea of extending the garage and planning ahead for it. What about pouring the slab for the addition and letting the shed sit on it for the time being?

Plan B would be some small concrete pads for those blocks to sit on, even some big pavers may do. My concern is those block things sinking under the weight of your 22'x 22' "shed"

First and foremost, call your local building department and ask what is required for building a shed. I guarantee somebody will care, if only so they can collect their $50 permit fee. Nothing more annoying than getting busted by the building inspector and having to undo work.

Most of those sheds don't have foundations. There is usually two 6x6's the length of the shed and floor joists laid crossways on top of that. In our area you don't need a building permit for these because there is no foundation.

Mine is about 12x8, its really old and was built out of oak framing and is still very sturdy.

I built a 10x12 shed this summer on my side of the state. What I was told was to used 4" of gravel under the treated floor boards.

Ended up pouring a slab as I didn't want a wood floor.

I used 9x18x4 solid blocks on a 2-3" gravel base for my 8x16 shed, spaced every 4' under a 2x6 PT platform with 3/4" PT ply on top. I looked at those molded blocks but it looked like they would raise the deck higher than I wanted. Plus, they cost 3x more than blocks.

Most twps. will allow a 100 sqr ft shed without a permit, but check first. We built a 10x10 shed at my ex's house and they didn't require a permit (no fee), but did want a plot-plan filed showing the location and set-back requirements.

Be careful with a poured slab. Sometimes that turns it into a "permanent structure" which has different rules. Again - check first. Most twps. have all of this stuff online and it can be found with a bit of Google-fu.

What they said

Out shed is just treated lumber on the ground. No issues.

Adrian_Thompson wrote: ... Obviously I'm not going to start until spring. Michigan in November is not my idea of ideal out door project weather. But I'm planning and sketching a modern shed....

Don't be such a Bob Costas.

This is all excellent news. I avoid actually talking to the city at all costs as they want to do annoying thinks like inspect what you are doing and adjust taxes accordingly.

LEvel, gravel and build. Roll on April.

Gearheadotaku wrote: I like the idea of extending the garage and planning ahead for it. What about pouring the slab for the addition and letting the shed sit on it for the time being? Plan B would be some small concrete pads for those blocks to sit on, even some big pavers may do. My concern is those block things sinking under the weight of your 22'x 22' "shed"

He he.

Future extension would be about 22x22 as you say, but I already have a poured walk way behind and store our sunfish and other stuff there. This will be about 10x12 or 10x14 and sit about 8' behind the garage offset away from the edge of the garage to help hide it. It will be mid century modern and look more like small hut than a shed using a huge approx 8'x5' window that we had replaced in the house on the side looking at the garden. Aesthetics will be high on the list. Look for a future build thread.

The town I live in requires substantial footings below frost line for sheds of a certain size and larger. I put in an 8'x14' shed so it didn't fall into that category. It's a pre-fab panel structure that 2 guys brought in on a truck and erected and completed in under two hours. No special prep to the ground was required, and they leveled it with concrete blocks and shims. That was June, 2014, and it's still as level as the day they put it up. My back yard has a few inches of top soil and under that is hard pan thanks to the glaciers (like concrete). You probably couldn't do that with soft soil. I love my shed. I didn't have to spend a lot of time stick-building it myself, it's stylish and compliments the architecture of my house, and most of all I was able to get all the clutter out of the garage.

But Adrian, aren't you also going to build a pub shed? That's my next objective, complete with small wood stove and porch. https://www.google.com/search?q=pub+shed&prmd=ismvn&source=lnms&tbm=isch&sa=X&ved=0CAgQ_AUoAWoVChMIoIPT66iJyQIVw1weCh0cdwNz

Our shed is prefabbed (what can I say, I'm a pansy) and we just found a nice flat corner of the yard, dug out a few inches of sod and put down 4-5 inches of crushed gravel on it. Tamped it down, watered it and let it set for a few days. It was VERY hard and solid, almost like concrete. Threw the shed on top of it about 8 years ago, no issues whatsoever. I'm in MI too.

I built a 8'x 12' shed (to get under the 100 sq ft) 20 years ago. Used 4 12' 4x4's and 5/4 decking for the base. Still solid as a rock even though I didn't put anything under it.

I helped a neighbor make a shed, his base was pre-loved railroad ties. $4 each.

914Driver wrote: I helped a neighbor make a shed, his base was pre-loved railroad ties. $4 each.

Where do you find them for $4 each, I see them for three times that price

He got them from a landscaper. I see brand new ones all the tie if you've got the nads to take them.

I would dig down a bit, fill with sand and use the extra large pavers as the floor surface for the shed.

914Driver wrote: He got them from a landscaper. I see brand new ones all the tie if you've got the nads to take them.

Getting them out from under those heavy rails is the issue!