I have a small 80 year old bungalow in an area of texas that gets cold in the winter and hot & humid in the summer. It has about a 3' open crawl space that could take on a few inches of water during a rainstorm. And of course there's the occasional hurricane that creates gale force winds ... under my house.
With that said, I'm looking for best insulation i can find. I was thinking about foam, but I'm not positive on how you would install that correctly.