In the past, on some multi-day climbs, I slept under a tarp, with my quilt and air mattress inside a bivy sack.  I also had other nights in a tent, in alpine country, with condensation  wetting out my exposed quilt.  Sometimes in shoulder seasons, my quilt isn’t quite warm enough.  Then this year I discovered a great source of ultralight fabric.  These were all motivations to try another project – an ultralight bivy, with options for bug protection and a cold weather liner.  I finished it and have now tried it out successfully on a cold night.

The fabric source is Ripstop by the Roll.  They offer a wide assortment of coated and uncoated nylon and polyester at weights as low as 0.56 oz. per square yard.  Continue reading →