Concrete Pilings to get below frost line?

[sharp21]

Hi all,

I worked one summer pouring concrete & when we did walkways we would use an auger to drill 4 foot holes every 6 feet or so to support it.

I'm looking at building a small outdoor kitchen & was wondering if I would employ a similar method to support it, rather than setting the foundation all the way down.

It will consist of a pizza oven, gas grill, fridge & potentially a sink. I live in central Alberta & the winters get COLD!

What other solutions other than full foundation do the Canadians here use?

Thanks
S.

[dmun]

Re: Concrete Pilings to get below frost line?

I believe that sonotube type protrusions from a slab is the worst of both worlds: they give ice lenses something to grab onto. I think the best solution for a freestanding oven is a slab on well drained crushed stone. The theory is that if there is no water next to the slab there is no frost heave. If you want to use sonotubes, they make a flaired form for proper base footings, but that's almost as much trouble as building footings below the frost line.

If you are building an oven inside, you will have to follow building code for masonry fireplaces, which means foot thick footings protruding six inches beyond the perimeter of your structure, poured on undisturbed soil. For a freestanding structure, I think it's complete overkill.

For a Canadian approach to the same problem, you can research "frost protected shallow foundations"