Ask about the woes of getting the goods, the crew, and the crane at the house at the same time.
Okay, so they're here. Now the SIPs go onto the roof.
But the crew gets the SIPs up there in jig time.
The middle part of that panel is extruded polyurethane - 5½ inches gives R-42.
Suppose the SIPs don't quite fit. What would you do?
If wacking it with an ordinary sledge doesn't work, borrow Tom's 18 pound black locust maul and beat the heck out of it with that.
Afterward, the gaps are sealed with expanded polyurethane.
Beyond the SIPs, the roof that didn't get covered is over the eave, beyond the interior of the house. Urethane is too expensive to use over eaves, but we have to put something there to make the roof flat.