Foundation Depth

[MikeD55]

Was wondering what the “best practice” foundation is for an oven in a cold climate. My experience tells me frost depth or lower. If so how would that look like?
-perimeter footing with CMU left hollow in the middle?
-perimeter footing with CMU filled with gravel in the middle?
-full pad with CMU all around left hollow in the middle?
-full pad with CMU all around and filled with CMU on top?

Slab footing seems to be popular on this site but I’ve seen some that work and some that don’t. I personally saw one last month in a cold climate that shifted 2”.

Talking strictly about the foundation and not the stand.

[mongota]

My experience?

I live in CT, so I get winter freeze/thaw. Frost depth here is 42".

My build is in a well draining area that has good subsoil that does not hold water, and the build is not in a low area of my property. I ended up going down about 28". Dug down, poured a perimeter footing. Then two courses of CMU, with that topped off with a slab.

Hasn't moved in the years since.

[MikeD55]

Ok thank you. Same here 42”

[RandyJ]

Hey Mike I am not sure where you are at but my call was to dig all top soil out then lay in 6 to 8" of compacted class 5 gravel the pour my slab. With the very hard clay in my area I didn't want to go through the effort to dig all the way down. I did basically the same thing on my last oven and never had a issue. I am just west of Minneapolis Mn so we get serious cold here. My sons treehouse is just on deck blocks and has not budge in 3 years so I am not going to worry.

Randy

[MikeD55]

Mongota

How thick was your footing???



Randy J

How high above grade was your slab?

[RandyJ]

MikeD55 I dug down about 12" to 14" and then had close to 8" of class 5 and the 6" to 10" of concrete. My slab is just above grade on one side and due to a bit of slop the other side is about 6" above grade. I also had a grid of rebar about 8" on center in both directions. If you want to see the pictures they are in Treehouse Pizza. That is my current build. I managed to go from ground breaking to a functioning oven in just about 2 months. That was a lot of work but glad I pushed it as now I'm stuck working over time and am very limited on ability to work on the oven.

Randy

[mongota]

MikeD55

Mongota

How thick was your footing???

Mike, I used a couple courses of 12" CMU on top of the footing so the footing was about 16" wide and about 8" deep. On undisturbed soil.