I knew that the PVC and SEN foam cores we use to build boats had some thermal insulation value but I didn’t think it was as good as house construction insulation foam. At the Fiberlay design conference I learned that it is almost as good as the insulation foams. For example 90 kg Airex is 0.24 BTU.in/sqft.hr.F which comes to R 4.2 per inch. Craig Riley tells me that the PET foam gets wildly even better results when in a vacuum.
I began building my first trimaran, Smoholla the Shaman the year that I began architecture school. That was 1977. I first sailed her the summer that I graduated. It was my home for a couple of years and at the same time, the fastest sailboat in Puget Sound, until Chaak came along. She was my CM construction method prototype.
She lives in the Chesapeake now, looking different but still sailing. How nice.