Filed under Cast Iron & Older Homes · By Michael and the team at The Irish Plumber
How long cast iron lasts
Cast iron drain pipe can last 50 to 100 years. How long yours lasts depends on the water, how the house has been used, and how the pipe was installed. Horizontal runs, especially under the basement floor, usually fail first, because water sits along the bottom of the pipe and slowly eats through it.
If your home was built before about 1970 and the drains have never been replaced, it's worth knowing their condition.
Signs your cast iron is aging
- Rust stains or flaking on visible pipes, especially at joints
- A crack along the bottom of a horizontal run
- Slow drains and repeat clogs, because scale builds up inside and catches debris
- Sewer smell near the stack or floor drain
- Water stains on ceilings below bathrooms
- Damp spots on the basement floor above the building drain
Why age matters
Old cast iron rarely fails all at once. It thins, cracks and scales until one day a section lets go. Then you may be dealing with sewage under the floor or in a wall, and an urgent repair instead of a planned one.
How are your cast iron pipes holding up?
A camera inspection shows the inside of your stack and drains, so you can plan instead of react.
Repair or full replacement?
A camera inspection tells you which sections are sound. If one section has failed and the rest looks good, a partial replacement can make sense. If most of the system shows heavy scaling, cracking or thinning, replacing it in one planned job usually costs less overall than a series of emergency repairs. It's especially worth doing before a renovation closes up walls and floors.
What replacement involves
Old cast iron comes out and new ABS goes in, to current code, with proper supports, venting and a cleanout. Floors and walls are opened only where needed and put back. How we replace cast iron.