The truth about building codes and home inspectors is a complicated issue. The Standards of Practice for the various home inspector associations do not require the home inspector to mention code violations when writing the report. However, most of the inspectors I know do recommend that some key items be code compliant when these items are either a health or a safety issue.
An updated code is issued every three years and there are separate codes for the major systems, i.e. plumbing, electrical and general building. It is up to the building department to adopt the new code as it is not automatically adopted. To view the codes currently being used by the County of Maui go to the Title 16 section of the Maui County Code at: http://ordlink.com/codes/maui/index.htm
A good example of a safety upgrade for older homes (25+ years old) is an electrical safety device called a GFCI electrical outlet. GFCI stands for Ground Fault Circuit Interrupter and this device is currently required at all water related areas of the home, i.e., kitchens, bathrooms, wet bars, sinks, crawlspaces, garages and exteriors. The device first became part of the code in the 1970's and was only required in bathrooms and garages. Later codes added locations such as exteriors, kitchens, crawlspaces and wet bars. So a home built in 1975 might have a GFCI outlet at the garage and bathroom, but at none of the other areas mentioned. I will always mention in my report when upgrades are recommended.
Another good example is the installation of smoke detectors. The first requirement for smoke detectors was to install one hardwired (120v) smoke detector in the hallways adjacent to the bedrooms. The latest code requires hardwired smoke detectors at each level of the home and in each bedroom in addition to the hallways adjacent to bedrooms. All smoke detectors in a home must be interconnected, so that if one of the smoke detectors goes off, all smoke alarms will sound simultaneously.