Some types of plumbing that are no longer used or are not up to current codes include:
- Galvanized steel pipes, which are prone to corrosion and reduced water flow over time.
- Polybutylene pipes were used from the 1970s to the 1990s but are prone to breakage and leaks.
- S-traps do not have proper venting and can cause clogs and sewer gas odors.
- Certain materials like corrugated piping and rubber fittings that do not meet current plumbing codes.