Awnings are attached to the house above the windows to provide shade. They typically have UV-resistant fabric stretched over metal frames, and can be fixed or operable. Some are fabricated from aluminum slats. Awnings block direct sunlight and glare from the window opening to reduce summer cooling needs. The greater the unwanted solar heat gain, the more cost-effective this retrofit will be. It is better to prevent sunlight from entering the home rather than try to mitigate its heat effects after it has already passed through the window.