Building a cottage with a walkout basement.
The cottage will not be heated.
I installed a frost wall at the front and back 12' on each side. The back and sides are backfilled 6' over the footings on the outside. The floor is 4" concrete and drainage is installed outside at footings.
Also I installed 2" of styrofoam in from the footing horizontally for 24" under the floor.
Will I have a heaving problem next spring?
We built in Haliburton Ontario.

best practice calls for this foam to extend out 4' for that far north.

Also, you description implies this is under construction and may not yet be framed over. With back fill in and no floor on, you could have frost pressure laterally on the back/side walls.

I would buy a dozen bales of hay to shake fluffed lose all over and then covver with plastic fo5r an additional layer of winter insulation

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