Solexx has the best insulation qualities of any product on the market, however, in order to achieve the R-Values; the ends of flutes must be filled with a ¼" bead of clear 100% silicone caulking prior to installation or after trimming an already attached panel. This traps the air inside the flutes. Unless you need to cut or trim the panels after installation, be sure the bottoms of the panels are caulked prior to installing as it is very difficult to point a caulking gun up ½" from the ground.