The first structural attribute to consider is the foundation. There are six different foundation types:

• Continuous wall with slab
• Crawlspace
• Piles
• Piers and posts
• Slab-on-grade
• Basement

This diagram shows examples of common foundation types. You can use it as a reference to determine the foundation type of a structure being assessed in the field.

The most common type of foundation will vary regionally.