In most cases, installing new skylights or a row of solar thermal collectors on an existing roof is pretty straightforward. That’s because most roofs are stick-framed and we know what to expect. I knew this roof was different, because I had built the timber-frame and structural-insulated-panel home 20 years before, but I was still surprised by some of the difficulties we encountered along the way.
For anyone not familiar with SIPs, most are manufactured of foam insulation sandwiched between sheets of oriented strand board. The roof panels on this home were made with 91/4-inch-thick polystyrene and were installed over an exposed timber-frame structure, with rafters and purlins spaced several feet apart providing support.
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