THERMA-TRU. The Energy Star-qualified Fiber-Classic Mahogany Collection three-panel door features the affordability of a fiberglass door with the look of premium mahogany graining. The doors feature U-factors as low as 0.18 and a SHGC starting at 0.05 and will not rot, warp, or fade, the company says. They come in fire- and impact-rated versions with four new privacy glass options and 17 decorative designs for the doorlites. 800.843.7628. www.thermatru.com.