- Factory-installed piping within service water heating equipment tested and rated in accordance with Section 606.4.
- Piping conveying fluids that is neither heated nor cooled, including cold water supply and natural gas piping.
- Hot water supply piping exposed under sinks, lavatories and similar fixtures.
- Hot water distribution piping buried within blown-in or sprayed roof/ceiling insulation, such as fiberglass or cellulose, where the insulation completely and continuously surrounds the pipe.
Exception: For piping other than that located under building slabs, insulation is not required where the insulation manufacturer stipulates that the pipe insulation will maintain its insulating value in underground applications in damp soil where installed in accordance with the manufacturer's instructions.