How do I protect my footings from frost?
Frost-Protected Shallow Foundations
- The footings of most foundations are placed below the frost depth.
- Either extruded-polystyrene (XPS) or denser types of expanded-polystyrene (EPS) insulation may be used to insulate a frost-protected shallow foundation.
How deep is a frost footing?
Most building codes in cold-climates require foundation footings be placed below the frost line, which can be about 4-feet deep in the northern United States. The goal is to protect foundations from frost heaving.
How much further down past the frost line should you put your footers?
As a general rule of thumb, you’ll need to place at least 1/3 the height of the post in the ground. For example, a 6-foot tall fence will need at least 2 feet of post in the ground.
Does frost penetrate concrete?
Frost heave can wreak havoc on concrete driveways, sidewalks, and patios around your home. As the frost within the soil thaws and melts, the concrete can settle back towards its original position; however, it may remain raised if uneven base material develops beneath the concrete or if sufficient sized cracks develop.
How do you prevent frost heave in concrete slab?
To prevent frost heave, there are two general ways to handle a slab: Drain it or insulate it. One way is to drain beneath the slab, so there is no water in the soil to freeze. This could be challenging under a slab connected to ledge, since groundwater often follows the contour of ledge.
Why do footings have to be below the frost line?
When you excavate your footings you will need to dig below the frost line. This is the depth at which the moisture present in the soil is expected to freeze. Once your footings are buried below the frost line the ground will act as a barrier to insulate the soil below the footing from freezing in the winter.
How deep do concrete footings need to be?
Depth of Footings Footings should extend to a minimum depth of 12 inches below previously undisturbed soil. Footings also must extend at least 12 inches below the frost line (the depth to which the ground freezes in winter) or must be frost-protected.
How much weight can a pier block hold?
A single 8” x 16” concrete block can carry 8,000 lbs. Don’t go over 36′′ high. The single blocks that can be used for your pier can easily carry 5,500 lbs. They limit a dry stack, single block pier to 5,760 lbs.
