
Every week, the detail-oriented folks at Green Scene Home Inspections will give Daltxrealestate.com readers an education in inspection. Want to see what they see? Tune in for “Upon Closer Inspection.”
When we inspect older homes, we often find original or “as-built” conditions that are no longer up to the current building code. As a homeowner (or home buyer), you’d want to know about this because 1) the material or installation is no longer considered safe and 2) replacing it may be costly.
Here are a few examples of things we’ve found that were considered OK when the house was built, but aren’t anymore:

Knob And Tube Wiring
Knob & Tube Wiring was the standard for electrical wiring in homes from about the 1880s through the 1930s when it was deemed both unsafe and more costly than cable wiring. We don’t often see Knob & Tube wiring, and even less often do we see it actually in use. This was found in a historic home and would be even more of a fire hazard considering the age of the equipment.

Cast Iron Pipes
Cast iron pipes first came into use in the US in the early 1800s, and you still see them in use in older homes. Unfortunately, cast iron pipes have a life expectancy, and begin to corrode over time. Replacing them can be pretty expensive. This is a corroded and blistered cast iron pipe, seen from the crawl space in a pier & beam house. You’ll see cast iron pipes in homes built before about 1980.

Grey Ductwork
Grey ductwork, or grey flex duct, is a product that was used in homes, mostly in the 1980s, as insulation for ductwork. It fell out of use by the early ’90s because the outer grey coating was found to deteriorate when exposed to high heat or UV rays.
Of course, that means attics are generally a bad place for it to function. This one has pretty much disintegrated.
Zinsco Electrical Panels
Zinsco was a popular brand of electrical panel in the 1970s. The company is now defunct, but some homes built in the 70s still have these unsafe panels.
Our inspector Brian demonstrates the danger using his thermal imaging camera.