You Can't Use the Existing Foundation.

No, you can’t use the existing foundations (but there are exceptions).

In Los Angeles, when you add a second story to a one-story house you’ll need new foundations (to help support the new second story)–no ifs, ands or buts (except for exceptions; and there are always those).

Our building codes are stringently protective against seismic collapse, and most one-story houses have foundations that are just not capable of supporting a second story’s weight and sideways movement in a quake. Read More...