1977 house. The LP water heater vent transitioned to an oval vent to vent to the rooftop from basement. The construction materials in this area was blackened (rim/floor/sill/subflooring). Heat from pipe causing moisture? Any thoughts/insight? I know the pics aren’t the greatest, but that’s all I got.
Not sure if the flue caused the black or not. Anything else that might dump into that cavity? Get that copper off that nail and put in proper supports…galvanic reaction.