I am Site-superintendant for a new developer on the Wa. coast. We are currently using POZZI aluminum clad double-hung windows on our residential homes. I am frustrated with the installation procedures, and unhappy with the design of the nailing flange. I know Andersen uses a continuous plastic flange on their fiberglass windows, but the designers don't like the interior construction of the "division bars". Does anybody know of an aluminum clad window that installs like a vinal window, using a continuous nail flange?