Of course, trees and shrubs can take years to mature. If yours are still too young to lend adequate shade, don't fret: Awnings achieve similar results, and they do so more or less instantly. Sure, not everyone loves the look of awnings, but few would argue against their effectiveness. Installed over a west-facing window, a fabric awning can reduce heat gain by as much as 77 percent! It's a simple concept, really: Block out the harsh sun to enjoy cooler spaces indoors.