Q's.. building 12x14 shed on concrete slab in Canada

Old 10-13-09, 10:31 AM
Thread Starter
Join Date: Feb 2009
Location: Canada
Posts: 16
Upvotes: 0
Received 0 Upvotes on 0 Posts
Q's.. building 12x14 shed on concrete slab in Canada

I want to build a shed, 12x14 in size. After realizing all the work/cost associated in building a wood floor, I've decided I would rather have a concrete floor.

I would like a 4" thick floor, reinforced with wire mesh. But I live in Canada where it gets very cold so my main concern is frost heave.

My friend says that instead of pouring a footing all the way below the frost line which is about 3-4 feet here, I can just make the slab thicker, about 8" thick, around the perimeter which will be supporting the weight of the outside walls. Then re-inforce this part with re-bar. This would allow the entire slab to sit above the frost line, and in the event of frost heave, to move as one.

We're not sure about is the proper way to prepare the foundation. What is the best material to use? I was thinking to dig a trench about 8-10" around the perimeter of the shed, fill that with 0-3/4 crushed stone, and compact it down to grade level. Then fill the middle with another 3-4" of crushed stone, so I'm left with a foundation about 3-4" above grade, sloping down to grade level around the perimeter. Then cover the whole foundation with 1-2" of 3/4 rock to give good drainage, and pour our slab on that.
Old 10-15-09, 08:00 AM
Temporarily Suspended
Join Date: Jul 2008
Location: NY
Posts: 10,265
Upvotes: 0
Received 0 Upvotes on 0 Posts
Your friend is right about the frost line. I don't know if the thickness of the slab & the mesh is a good way to avoid the footing. If you are going to have an 4-8" slab with a footing, I'd have a truck do the pour. I wouldn't mix all that myself.

Thread Tools
Search this Thread
Ask a Question
Question Title: