We have a wall of window and some of them are 30 ft up. Conventional curtains will not work. We have not been able to install yet as our tall ladder broke, but I tried a piece on another window to see how it would apply. It was super easy to install! It does change the color to a muted gray, but it does work as you can see in my pic. It created a shadow where the material was installed. Can not wait to get it on the window that creates a glare in the sunny afternoons! Ignore my dirty widow sill..