Your Addition

[garyl62]

Too bad about drilling into the pex line for your addition, hope the repair is going well for you. My question is about the lack of footings. Always assumed you would have used a frost footing not just a thickened edge of a floating slab. Especially since it looks like you have plumbing in the addition, and you have heat lines running though it. Do you figure that since you are heating the slab and your soil drains well you don't need it? Is that common up there? As you well know, down here in N. ILL we go at least 42" deep for our footings or else we have trouble with things moving on us.

 

[jd]

Keweenaw County is one of the few places that I know about where you can build a residence on a floating slab. I think it has a lot to do with the fact that we get snow on the ground before it starts to get really cold and the frost just does not penetrate very deeply. The "frost line" for building codes here is 48", but unless you are plowing the snow off that area of ground, the frost penetration is quite shallow and in some winters we really do not have much frost penetration. I have heard of locals leaving their root vegetables in the ground and picking them all winter to eat.

The slab being heated and also the fact that there is around 2 feet of sand surrounding the slab also leads to it being stable all year long. We have been in this home for almost 7 years now and not a single drywall crack or pop.

-John