In the late 1950s a product known now as chicago siding was introduced. It was introduced by an independently owned manufacturing plant in Columbus, Ohio. Its been making waves ever since. In Canada and America, it's the number one exterior facing for a house. In the united kingdom and New Zealand there's a similar substance called weatherboarding that is uPVC.
It's the number one siding in both America and Canada now. There have already been changes in the production, impact resistance, range of colours available, and the chance of fading due to exposure to UV light was reduced.
The chicago siding of now is made in a constant procedure in two layers of PVC. The bottom layer is referred to as substrate and the top layer is called weatherable capstock. Weatherable Capstock is where the break and color down and resistance to UV are found. It'll still disappear over time, but at a considerably slower rate than its forerunner. While neutral colours have a considerably slower rate there exists a higher rate of disappearing in the colours like Barn Red. Take care when selecting your color you need to love it and as it'll change somewhat over the last few years.
Inquire about the UV coating that's used. The UV coating that produces apply to the siding can affect the life expectancy of the product. If the UV coating isn't applied the light in the amount will degrade the siding quicker.