Since a SIP is basically like an I-beam type of setup, it relies heavily on the EPS foam core for its strength. The downside is that EPS begins to melt around 165F – 180F. Once the foam fails, the structure fails/collapses.

Has anyone observed or read about a SIP roof or SIP wall home being involved in a fire? If so, what was the outcome?

What’s the hottest temperature that a SIP roof can get? I assume in the desert southwest a SIP with a metal roof on top can see some high temps. Is it hot enough to melt the EPS core?

Lastly, some SIP companies push PU for the core since it can take higher temps, up to around 300F before it melts. Does that make PU SIPs the better choice over EPS SIPs?