Spray Foam Insulation In Residences
Spray Foam Insulation In Residences
NEMA Bulleting No. 95 - Thermal Effects of Type NM-B Cable Encased in Spray Foan Insulation Used in Residences addresses this issue.
However, I am dealing with an issue regarding XHHW service entrance cable.
Approximately 2 feet at each end of the cable in encased in the spray foam - where the cable leaves the meter base and where it enters the remote panel. The rest of the cable runs through a fire-rated floor ceilng assembly. The spray foam insulation is BioBased 501. In tests, it will begin to char at temperatures exceeding 400 degrees Faranheit and has an ignition point of 700 degrees Faranheit. The Alcan Stabiloy cable is suitable for operation at 600 volts or less at a maximum operating temperature of 90 degrees Celsius which equals 194 degrees Faranheit. I am a Builder and not an electrician but I would think that the circuit breaker would trip before the temperature would ever reach 400 degrees.
The inspector wants me to produce a report from an acceptable testing agency showing that the this installation has been tested. He will not accept a letter from the insulation manufacturer.
Any suggestions.