Cast Iron Drain Pipe - Life Expectancy

Inspected a home here in Florida yesterday, original iron drain pipe, constructed in 1960. Observed a previous repair to the pipe at guest bath(above slab). Significant rust. Got me thinking about the life expectancy which I’ve read is 50-60 years, correct me if I’m wrong. When you old salts inspect a house like this do you write up the fact the drain lines may be nearing the end of their useful life? I mean typically I don’t get a view of the drain lines, either concealed in wall or under slab. Any input is appreciated.


Cast iron drains are close to the end of their life and are prone to leak at any time .
Recommened budget for immediate replacement .



  • Although PVC and clay became the piping material of choice a few decades ago, because of the long life span of cast iron, some homes and buildings from the 20th century, and even earlier, are still equipped with this type of sewer line. Good quality, thick cast iron piping, installed under idyllic conditions can last from 75 to 100 years and beyond. Manufacturers now make ductile iron sewer pipes and fittings, but in contrast to cast iron installation of the past, the new metal waste disposal system is as quick and easy to mount as PVC sewer piping.

Read more: What is the Life Cycle of Cast Iron Sewer Pipes? |


I simply put cast-iron and galvanized piping will rust from the inside to the outside and eventually will need updating. If mineral deposits are noted as reported as a leak. Also be aware I have found vent pipes totally rusted out behind the wall. Typically you will smell an odor in the bathroom if this occurred.

Please note if you had Sean Fogarty working with you it may be just that he dumped the load forgot air

Dam that sounds potent. :slight_smile:

Thanks guys