Here's what Randy responded to me if it helps.....
"As far as the hammock itself.
- Double layer makes it MUCH easier to sleep on a pad. They tend to squirt out from under you in a single layer hammock,
- Once you reach the point of having enough fabric under you for safety and good support, more or thicker fabric doesn't help much. I list comfort ratings rather than weight capacity because I'm more interested in what fabric will give you a solid, flat lay. I'm 265lbs and I can lay (uncomfortably) in a single layer 1.1oz hammock. It holds my weight, but is obviously, not enough fabric for me.
- At 175lbs, you could actually get away with as little as a single layer 1.1oz. The 1.8oz Taffeta would give you a nice flat and solid feeling hammock. If you decided on a double layer, you may consider a DL 1.1oz because the heavier fabrics would kinda be wasted weight for you.
My 1.8oz Olive taffeta is a high count fabric, meaning it's built with a higher number of individual fibers. It has a softer, smoother feel and I like it quite a bit. You can see some photos of this fabric holding my 265lbs on this page of my website.
http://www.dream-hammock.com/Darien.html The (guy) in the Olive hammock is me. You can imagine the support you'd get with a hammock made from this stuff."
Hopefully, this helps you out a bit. Again, he's (Randy) is super responsive just ask away!