Using Freznel Water for glass

What is glass? It has almost no color, it reflects it's environment and it reflects light. That's why I use a very bright blue as the basic glass color (RGB 245, 255, 255) and a tone similar to the sky color for the reflection. The normal shader is fine with most *exterior* rendering setups.

The problem is that often glass is not equally thick resulting in a wavy reflection. Because of that I recommend using the Freznel Water shader. It takes a little longer to render of course, but unless you have consecutive layers of glass you won't notice on faster machines. Find my settings on the left. The result will look as shown in the screenshot.