A.Bill Wachtler, executive director of the Structural Insulated Panel Association, responds: In general, temperatures would need to exceed 190°F before any degradation of a SIP would be possible. In a typical roof application, it’s hard to imagine that there would not be sufficient dissipation of heat to prevent temperatures from rising that high.
Nevertheless, there are preliminary reports of at least one house with a copper roof installed over SIPs that developed problems requiring investigation. That investigation is ongoing, so no conclusions can be made yet. In the meantime, I recommend checking with the copper roofing manufacturer and supplier, as well as the SIP manufacturer,...
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