Age Chart

I’m going to develop a reference chart of component / system features that are characteristic of the time period of construction. Before I do, has someone already done this and willing to share or have thoughts of how to organize the information. I’m debating to categorize by date ranges or by systems.

I know there will be overlap but in general it might be a handy reference chart to add to your collection.


Rating 200 > 1980

Service Lead < 1950

DWV Cast < 1960

Thanks guy but I’m not looking for life expectancy. I’m looking for a chart that characterizes what components / system are used for that time period of contruction.

When I inspect a home of 1920 for example what are the materials/ components / system unique for that construction / time period…



  • K&T used from what year to what year.
  • fused breakers
  • 2 Prong ungrounded


  • Lead service pipe

Polybutylene: 1978-1998
Ungrounded Outlets: Before 1965