I am making a synthetic quilt using Apex 2.5 for insulation. I selected very light fabric for the inner and outer fabric – 0.66 oz/yd Membrane 10 from Ripstop by the Roll. The quilt is going to have the drawcord type design (like the Enlightened Equipment Prodigy and Enigma) and I will use a fabric flap with snaps to close up the foot box about 18″ the bottom of the quilt.
Since this fabric is so light, I wanted to reinforce the seams and use a heavier fabric that I picked up from my local fabric store for the drawcord channels since these will have some abrasion from the drawcords. The fabric is a ripstop nylon that I estimate to be about 1.5 oz/yd. I am also a bit obsessive about protecting the raw edges of fabrics so I wanted to design a seam where the raw edges are tucked inside. Here’s what I cam up with:
Seam for drawcord channels and the footbox flaps:

And here’s the design for where the pad straps and other snap closures will be attached (using grosgrain or elastic):

I wasn’t sure whether the two lines of stitching shown in the picture will disperse the tension on the grosgrain/elastic enough to prevent the Membrane fabric from tearing. I could sew a box with an x to provide additional reinforcement.
Hoping for feedback on this point and on the general seam design.







