Hello,
I have been in the vinyl industry for 10 years and seen it all! I would like to echo what some of the users are saying: vinyl should NOT break in the cold. Any vinyl that does is inferior and cheap and doesn't have a good warranty. If you avoid the thin stuff (which includes the low grade stuff at the box stores), you should have a vinyl fence with a lifetime warranty against any cracking and splitting- even in the cold. Make sure you look for the warranty! You'll pay a little more for the good stuff, but be glad you did over the years. (Incidentally, in my area Home Depot doesn't even offer their off-the-shelf stuff in their installed program! They use an upgraded product. That tells you a lot right there.)
I would recommend that you contact local fence installers and find out who offers quality. There are many great vinyl fence manufacturers out there. Some of these companies include but are not limited to Westech, Country Estate, Certainteed (Bufftech), and Enduris. Most manufacturers that supply professional fencers don't thin down or cheapen their product. The company I worked for previously bought vinyl from Westech and Enduris and never had a warranty claim in the 7 years I had worked there.
You can also save money doing it yourself! That's what my company specializes in- a DIY vinyl fence project that requires no special equipment engineered and designed for a homeowner. It has a lifetime warranty and is professional grade vinyl.
It's like most things- you get what you pay for!
Good luck!
Denise
WamBam Fence