Originally Posted by sclittlefield
Ripstop just means that there is a grid pattern of heavier threads to help stop rips from spreading. It's a type of weave, and can be found in lots of different "formats".
Silnylon is Ripstop nylon that has been saturated with silicone to make it waterproof. That's the key, whatever you use, it has to be waterproof.
You can get ripstop with urethane coating, that will work as well.
Uncoated Ripstop will not shed water. It's great for a hammock, horrible for a tarp.
Okay, and sorry for all the questions, but I ordered this ripstip from my wife's wedding fabric wholesaler. He didn't actually know the weight of it, and I don't know if it's got urethane coating, but one side seems to be more 'plasticky'. And I'm wondering if that is urethane coating. I know it might me hard to tell without seeing it but maybe my description will help. If it is urethane, I'll order some more to make me cat tarp.