Adopted Codes


Williamson County is currently under the 2015 edition of the International Building Code for all commercial, educational, and assembly occupancies. For all residential construction, the 2015 International Residential Code© applies.  
  • 2015 International Building Code
  • 2015 International Mechanical Code
  • 2015 International Plumbing Code
  • 2009 International Energy Conservation Code

Plans submitted for residential occupancies covered by the 2015 International Building Code that are one (1) or two (2) story(s) in height having a gross area of less than five thousand (5,000) square feet must be significantly detailed and describe the site, foundation, framing, electrical, plumbing, mechanical, and sprinkler systems,

Note: Plans are not required to be designed by registered design professionals unless the project's complexity warrants otherwise. Buildings larger than this require plans to be developed by a registered design professional.

Additional Requirements

All Educational occupancies, Daycare facilities and large assembly occupancies must have plans approved by the Tennessee State Fire Marshals Office prior to permitting.