plastic extrusion material selection??? Hey all, I work for a curtain wall manufacturing and design company out of Canada. I've recently been presented with the task of creating a new extrusion to improve the thermal performance of our curtain wall system. My question to you all is, and excuse me if this isn't a very advanced question, what would be a good choice of material? I am looking for a strong, resilient, and thermally sound (low transmission of heat) plastic. We currently use PVC, but are interested in moving to another material due to some of the complications with PVC in a structural setting. Any help would be greatly appreciated. Thanks.