I have long been skeptical of radiant barrier products. I was completely surprised when I found that the shell building I inspected yesterday was 80-90 degrees inside. It was 106 outside!!! The only possible explanation was the West Fraser Solarbord decking. The building had no ceilings, no wall insulation, no gypsum board. The windows and doors were not caulked. The windows were low quality, dual pane (not Low-E) and faced south and west. I really expected it to be beyond sweltering when I arrived at 1:30 p.m. I had to insist that the door be kept closed to keep the ‘cool’ air inside. I plan to specify this product on future projects.