eVent is a waterproof and highly breathable fabric. It is also completely air-permeable, making it ideal for use in sleeping bags.

Modern technologies have produced numerous fabrics that can be called waterproof and breathable, but only one came into consideration for our crux sleeping bags – eVent. We started using eVent back in the late ‘90s (before it was even launched and while we were still working for another major outdoor brand) and were immediate converts. The breathability of eVent is far superior to any other waterproof/breathable fabric regardless of the technology used (i.e. membrane or coating).

What is unique about eVent is that it is an air-permeable laminate (others, such as Goretex are not). This means that the air can be pushed through it – important for sleeping bags when compressing them into a stuff sack. But the fabric itself is still completely windproof.

We use a two-layer construction that comprises the outer face fabric and the eVent membrane. The face fabric has a very smooth “spuntouch” finish that we prefer for two reasons: durability (a smooth surface has better abrasion resistance) and the ability to hold a good DWR (Durable Water Repellent) coating. With a weight of 80 g/m2 and using 40 denier yarn, hence twice the weight and thread size typically found in standard down sleeping bags, this fabric also affords a greater degree of protection from rips and tears. This is also the most breathable eVent fabric available. Finally, it is also remarkably soft. This means that, unlike most lightweight waterproof fabrics used in sleeping bags, it does not rustle. It is very quiet to sleep in.

For more information on eVent fabrics, please click here