Quick Answer
Mylar bivys typically maintain their integrity under heavy snow, but the weight and moisture can cause the material to sag or shift, and potentially compromise the waterproof seal. In ideal conditions, a Mylar bivy can withstand up to 10-15 pounds per square inch of pressure, but excessive snowfall can push against the material. Proper anchoring and staking can help mitigate this issue.
Understanding Mylar Bivy Material
Mylar is a type of polyester film used in bivys due to its waterproof and wind-resistant properties. When exposed to heavy snow, the material can become translucent and develop small pinholes, but this doesn’t necessarily compromise the waterproof seal. In fact, Mylar is more resistant to wind-driven snow than traditional nylon or polyester fabrics.
Handling Heavy Snowfall
If you’re using a Mylar bivy in a snowy environment, it’s essential to secure it properly with stakes and guy lines. Aim for a minimum of 5-6 stakes per corner, and use at least 2-3 guy lines to prevent wind-driven snow from lifting the bivy. You can also use snow anchors or snow stakes to distribute the weight of the snow more evenly.
Preventing Moisture Buildup
To prevent moisture buildup inside the bivy, make sure to keep the interior dry by storing gear and equipment outside. If you need to enter the bivy, remove your wet clothing and dry off before entering. Keep the bivy entrance area clear of snow and debris to maintain a clear airflow path, and use a breathable ground cloth to help regulate humidity levels.
Find more answers
Browse the full Q&A library by topic, or jump back to the topic this question belongs to.