The vintages in the Explorer represent the calendar years of the effective dates of the energy code under which the building was originally permitted for construction. Those years generally correspond to the effective dates of the three-year code cycles, but not always.
Usually, the nominal code cycle becomes effective on January 1 of the following year; for example, the 2019 Code went into effect on January 1, 2020. However, there are exceptions. In a few cases, the effective date of the code was postponed until mid-year (e.g., code cycles 1991 and 2010); and the 1978 code become effective on July 1, 1978. For the sake of simplicity, the Explorer assumes that any home permitted during a year that straddled code cycles would fall under the newer vintage code.
The table below provides details.
|
|
| Vintages |
Cost Effectiveness Study | Pre-1978 | 1978 - 1991 | 1992 - 2010 |
Nominal Code Cycles | None | 1978, 1981, 1985, 1989 | 1992, 1995, 1998, 2001, 2004, 2007 |
Effective Dates | Pre 7/1/1978 | 1/1/1979 - 8/13/1992 | 8/14/1992 - 7/1/2011 |
Permit Years in Ordinance (effective date rounded down for partial years) | Pre-1978 | 1978 - 1991 | 1992 - 2010 |
Citations
Building Code Cycles: https://www.dgs.ca.gov/BSC/About/History-of-the-California-Building-Code--Title-24-Part-2
1978 Energy Code Cycle: https://e2e.uchicago.edu/pdf/workingpapers/WP031.pdf
1992 Energy Code Cycle: https://avelar.net/an-abridged-history-of-the-statewide-california-building-code/