This page gives info about foundation excavation, types of foundations American Ingenuity design team can design and foundation resource.
For information on foundations used for the American Ingenuity Domes click on Foundation Summary, Concrete SlabPilings, Basements  and  Raised Wood Floor.  American Ingenuity Domes can be built utilizing the same foundation choices as conventional housing.
The foundation types that Ai designs are a) a monolithic concrete slab; b) poured footing with a stem wall and then a poured slab on fill;  c) poured footing with a stem wall and then a raised wood floor; d) basement and; e) pilings and a platform. The type of foundation that is built for your new home will depend on which is more advantageous for your area and what you soil’s report requires.
For American Ingenuity to design any foundation other than our standard monolithic concrete slab, we must hire a local engineer.  The engineer wants to view your soil report.  In the soil report a soil’s engineer will analyze your soil tests and recommend the type foundation that should be built.  The engineer uses this data to provide Ai information & details to be included in your foundation design.
About soil compaction:  Generally the soil under the foundation is compacted to 98% density for a minimum of 2000 pounds per square foot of bearing pressure.  Clean, compacted fill with no subsurface vegetation or voids.  If your soil cannot compact to 2,000 psf, then the footer will be designer larger and the slab might be 6′ thick instead of 4″ thick if acceptable by your building department.
Misc. Foundation Info

The following information came from the book, The Complete Idiot’s Guide to Building Your Own Home, second edition by Dan Ramsey. Any sentences that are in italics were added by American Ingenuity.

Excavating for the Foundation:

Houses require foundations. Why? Foundations support and stabilize the walls and roof. That’s a pretty important job! Excavation is the removal of soil to make room for the building’s foundation. So before excavating, let’s learn about foundations.

The foundation itself needs a foundation. Most houses are so heavy that the foundation must be widened at the base to keep it from sinking into the ground. (An American Ingenuity Dome shell weights less than a conventional house shell due to the thin concrete on its panels.) The wide part of a foundation is called the footing. Its size depends on the kind of soil under it. Most footings are designed to carry 1,000 pounds per square foot. A two-story house will have a wider foundation footing than a single-story house. Typically, the footing is twice as wide as the wall. That is, the footing for an 8-inch foundation walls is usually 16 inches wide. However, don’t go by this; go by your house’s foundation plan.

The foundation wall can be just 1 foot tall or it can be, with support, 10 feet tall or more. Or it can be shorter on one side and taller on another. It just needs to be level on top where the floor will be installed, which I’ll tell you about in the next chapter.

How tall and wide is the foundation for your home? Refer to the foundation plans approved by your building department. It will include the foundation’s layout, dimensions, size, elevation and height.

A slab foundation is a solid floor set directly on the soil. Most modern garage floors are concrete slabs with a continuous wall foundation around the perimeter.

A pier foundation is a series of concrete piers and footings that support the structure. If made of pressure-treated wood, it’s called a pole or post foundation.

It’s important to know the type and size of the foundation now because it tells you what soil needs to be removed or excavated for the foundation. It’s best not to remove any more compacted soil than necessary when excavating for a foundation. The more the earth has been disturbed, the more difficult it is to ensure that the foundation won’t move in the future.

Valuable resources as you excavate for and install your home’s foundation include the following:

  • Local building department
  • Building material suppliers
  • Excavation contractors
  • Transit-mix concrete suppliers
  • Foundation contractors
  • Backhoe and loader operators
  • Construction engineers
  • Concrete block manufacturers and suppliers
  • Construction tool rental yards
  • Alternative foundation sources (treated lumber, stone)
  • The many websites, books, videos, and magazines listed in Appendix B

If you want to know even more about foundations, check bookstores or www.MulliganBooks.com for a copy of my book Builder’s Guide to Foundations and Floor Framing (see Appendix B). It includes lots of illustrations, tables, and in-depth information on all types of residential and light commercial foundations.

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