- $5-7/sf -  
- A slab foundation already includes a floor - so cost would cover two elements of the building
- Although a concrete foundation can get expensive in areas with deep frost lines, a frost protected foundation only needs to be 18 in deep. This means that the cost of a slab foundation in the South and Midwest would be about the same.
- Concrete foundations can support 1 or 2 stories without added cost
- House foundation - $7 - 
- National average $9 - 
- $7300 to $8800 for 1000 sf - . Excavation and gravel not included.
- Needs gravel - $1k. $600 for 1000 sf 6" deep at $20/yard 
- Grading. 60c-$1.25/sf prep - 
- Seed Home 2 budget costs $3111 for foundation per module -  - so $12444 for 1000 sf. Because this includes the floor. Concrete slab is both foundation and floor.