The History Colorado website contains a wealth of useful resources for preservationists. Visit their website at www.historycolorado.org/preservation-archaeology
The Secretary of the Interior's Standards are the guidelines for the preservation, rehabilitation, restoration, or reconstruction of historic properties. http://www.nps.gov/tps/standards.htm
Preservation briefs provide guidance for the preservation, rehabilitation or restoration of different features of historic structures. http://www.nps.gov/tps/how-to-preserve/briefs.htm