- Concrete footings 101
- Bearing capacity of soil
Understanding soil type and bearing capacities
- Footing size
How to determine the minimum size for soil conditions
- Footing problems
Pouring in wet soil and more
- Frost heave & foundation footings
- Frost protected shallow footings
- Related Information:
- Concrete calculator for footing pours:
Figure out how many cubic yards you'll need
- Foundation drains for concrete footings
History of Frost-Protected Shallow Foundations
Frost protected insulated footings were used as early as the 1930s by Frank Lloyd Wright in the Chicago area. But since that time, the Europeans have taken the lead in applying this concept over the last 40 years.
There are now over 1 million homes in Norway, Sweden, and Finland with insulated shallow footings which are recognized in the building codes as a standard practice.
In the United States, insulation has been used to prevent frost heave in many special engineering projects (i.e., highways, dams, pipelines, and engineered buildings). Its use on home foundations has been accepted by local codes in Alaska, and it has seen scattered use in uncoded areas of other states. It is likely that there are several thousand homes with variations of frost protected insulated footings in the United States (including Alaska).
To verify the technology in the United States, five test homes were constructed in Vermont, Iowa, North Dakota, and Alaska. The homes were instrumented with automated data acquisition systems to monitor ground, foundation, slab, indoor, and outdoor temperatures at various locations around the foundations. The performance observed was in agreement with the European experience in that the insulated footings prevented the foundation soil from freezing and heaving even under rigorous climatic and soil conditions (ref. U.S. Department of Housing and Urban Development, "Frost Protected Shallow Foundations for Residential Construction", Washington, DC, 1993). A copy can be obtained by clicking here.