Tennessee is a "home rule" state which leaves adoption of codes up to the local codes jurisdictions. State energy codes are passed through the legislature, apply to all construction and must be adopted locally before they are enforced. In May 2008 SB 116 was enacted, mandating state-wide use of the 2003 IECC beginning January 1, 2009. This code was later updated to 2006 IECC effective July 1, 2011.
SB 2300, signed in June 2009, made changes to the state's building code policy and granted the State Fire Marshal authority to select the specific IECC code edition to be implemented. The bill does not reference the IECC, instead establishing the IRC and IBC as adopted codes. The bill includes a sunset provision and includes a mechanism through which local legislative bodies can "opt out" their communities with a two-thirds vote.
For new construction and additions to state buildings, the energy efficiency provisions (Chapter 13) of the 2006 International Building Code (IBC) will be replaced by ASHRAE Standard 90.1-2007