The 2009 and 2012 International Energy Conservation Codes (IECC) yield positive benefits for Colorado homeowners. Moving to either the 2009 or 2012 IECC from the 2006 IECC is cost-effective over a 30-year life cycle. On average, Colorado homeowners will save $1,528 over 30 years under the 2009 IECC, with savings still higher at $5,435 under the 2012 IECC. Each year, the reduction to energy bills will significantly exceed increased mortgage costs. After accounting for up-front costs and additional costs financed in the mortgage, homeowners should see net positive cash flows (i.e., cumulative savings exceeding cumulative cash outlays) in 2 years for the 2009 and 2 years with the 2012 IECC. Average annual energy savings are $119 for the 2009 IECC and $392 for the 2012 IECC.