Slab on Grade
Slab on Grade
(OP)
I am concerned about frost problems on a a 15'x25'x 4"+ thick slab on grade (on well drained sand-gravel mixture soil)for a detached, unheated with open sides to the elements structure we would like to build. The frost line in this area is aboud 42".
Any recommendations would be appreciated.
Any recommendations would be appreciated.





RE: Slab on Grade
Most severe heaving probems occur in silty soils.
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"...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail."
Wm. Phelps Eno, ca. 1928
RE: Slab on Grade
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"...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail."
Wm. Phelps Eno, ca. 1928
RE: Slab on Grade
That will have a great impact on frost penetration depth.
In Canada a slab on grace is typically insulated with rigid polystyrene insulation on the outer face to 2’ below grade with a a board on the flat for 4’ out from the insulation.
A lot depends on how the building is heated and an economic analysis on how to minimize total costs.
For an un-insinuated open building there is not much you can do about it. Well drained soils are usually not frost susceptible. Make the slab a little thicker to resist any localized soil movement.
Rick Kitson MBA P.Eng
Construction Project Management
From conception to completion
www.kitsonengineering.com