Yes. Due to the extremely expansive soils in this area, foundations (new and addition) must be designed by a State of Texas Registered Professional Engineer. The only exception is for residential additions of 400 square feet or less where it can be verified that the original foundation was not engineered. In these rare cases, a standard foundation detail (provided by the City), or equivalent may be used.
Building Permit application
Building Inspections 817.410.3165