Denver has officially adopted the 2009 IBC plus 2009 “I” Codes and published the 2011 Denver Amendments as of June 20th 2011. The City is currently under the Transition Rules for the next four months, with the hard adoption being October 17th, 2011. So until then you have the option of using the 2006 IBC + 2006 “I” Codes with the 2008 Denver Building Code Amendments or the 2009 IBC + 2009 “I” Codes with the 2011 Denver Building Code Amendments. Any project submitted to the City of Denver between June 20th and October 17th 2011 may be reviewed and permitted under the 2008 Denver Building Code.