Here is an interesting product for owner-builders. A liquid EPDM roofing that you roll on.
http://www.liquid-roof.com/new/index.html
The website has lots of information and a can of this sitting around could fix a lot of problems on your roof, boat or RV. EPDM sheets are considered one of the very best waterproof membranes. This is a thick liquid that makes the same surface in place.
Yes. I'm not sure but what there's another company doing these. One that does list their product for potable water. Didn't see it here.
Not cheap. If you buy the stuff they recommend for residential roofs--opposed to trailer, where you can buy smaller quantities--there's a 25 gallon minimum. At somewhere a bit above 200 sf/gallon coverage, most of us would need to go in with somebody to buy it.
Yes we used the product twice already. I have to say unbelievable. the first roof has been on for over a year and this is the first material we used that held up over the winter. Thanks again
Welcome to the forum -- thanks for the report. :)