That particular material is the same as the construction industry uses to wrap houses for water protection. It comes in several name brands and if you get the right material (there are several) I think that it would offer water proof properties. The material is very stiff (a washing does help) but over time it gets a little better. I have the same material that I use for wet conditions under my sleeping bag and it only weighs in at around 1 oz...

The first step that you take will be one of those that get you there....