I am a beginning to intermediate backpacker. I have gone camping on occasion over the past 10 years. I have started going on backcountry trips over the past 1 1/2 years. I also go on day trips in Illinois and Indiana. I am also a photographer and I try to have my hobbies go well together. While I am lightweight for a serious photographer (manual SLR, 2-3 prime lenses, Ultrapod, and occasionally either a compact tripod or a relatively light full sized tripod) the volume and weight of this effectively removes me from the ultralight backpacker category. My total weight (everything but the clothes I'm wearing) for a weekend fluctuates between 25-40 lbs (11 - 18 kg) depending on season, how serious I happen to be about photography and cooking on that trip and who I am with. Since I've already given up on ultralight, I usually give myself the luxury of a tent, sleeping pad, cooking stuff and an alcohol stove.

Product Description

Integral Designs eVent South Col Bivy (2003)
Regular, left-sided zipper
Color: Gold (Note: product tag states Yellow)
Maker: Integral Designs
Website: http://www.integraldesigns.com

Specifications (Website):
Length: Regular 84 in (2.1 m) fits to 6 ft 1 in (1.85 m)
Width: 32 in (.8 m) at shoulders tapering to 22 in (.55 m) at foot
Girth: 69 in (1.7 m)at shoulders tapering to 55 in (1.4 m) at foot
Weight: Regular 20 oz (.6 kg)
Packed: 8 in (20 cm) long x 5 in (12.5 cm) wide
Price: USD $235 (Regular)

Measured:
Weight: 20 oz (.6 kg)(including stuff sack)
Length: 84 in (2.1 m)
Width: 30 in (.75 m) at opening, 20 in (.5 m) at foot
Packed: 9 in (23 cm) long x 5 in (12.5 cm) diameter
The Integral Designs eVent South Col Bivy is a bivy sack made up of a waterproof and breathable top and a nylon floor. A waterproof side zipper runs about halfway down one side and there is a standard zipper across the top near the head for entry. The top zipper also provides adjustable ventilation through the use of a double slider zipper which allows for the user to have an opening of any size at any position along the zipper. While the fabric making up the top of the bivy breaths, the bivy comes with instructions to leave a 2 in (10 cm) opening in the top zipper to provide ventilation. A wire hoop runs alongside the top zipper to provide support for the fabric near the head. Versions of the eVent South Col bivy exist for both left and right side zippers to match a sleeping bag and in regular and long sizes. The bivy is intended to provide additional warmth to a sleeping bag as well as protection from wind and precipitation, especially when a full tent is not being used.

Testing

Location: Laural Highlands (SW Pennsylvania)
Weather: Light winds, light snow. Hi 40 F (5 C), low 30 F (0 C).
Used with a MSR Twin Peaks Tarp, Therm-a-Rest (Discovery Series) and a Sierra Designs Delta Fastbag, rated at 45F (10C).
This trip was done relatively lightweight (at least for me). Temperatures were expected to dip into the 30s F(~ 0C) while the Fastbag was rated at 45F (10C). (The fastbag consists of a nylon groundsheet zipped to what is intended provide an additional 15F (10C) of insulation to a normal bag while the Polarguard lid warms the top.) I attached the Fastbag to the Therm-a-Rest and stuffed the whole thing into the bivy. I used the South Col Bivy on flat ground which was covered by leaves. In addition I had a ground cloth under the bivy and I set up an MSR Twin Peaks tarp to block the wind and the expected rain that night. (I am still not brave enough to be out in the open in the rain.)

On this trip, I deliberately underpacked on sleeping gear to test the bivy's warmth. At night it dipped well below the rated temperature of my bag. In addition, the concept behind the sleeping bag I was using meant that it only had insulation on top. Any movement in the bag essentially exposed my sides to the outside, with only a layer of nylon for warmth and the clothes I wore (short pants and a long sleeve shirt). That said, the bivy did very well. I could hear the wind outside and coming through the tarp, but I did not feel its effects inside the bivy. I did get a chill from the cold when I turned, but not wind (i.e. the bivy does not provide actual insulation, of course, it was not expected to either). Initially it did feel stuffy because I had zippered the bivy completely,. However when I used the double slider to make a 2" (5 cm) openings as suggested, this was much improved. Nor was there a feeling of claustrophobia, as the wire kept the fabric off of my face.

In the morning I unzipped the hood to pull clothes into the bivy to warm them up. This involved opening up the top zipper all the way then sitting up. The opening when I did this is quite sufficient to poke my head and arms out and pull clothes from my bag which was next to me. There was some condensation on the bivy, but not much.

Overall, I was pleased with the use of the bivy. I've never used such a thing before, and its use with a tarptent frees up weight and space for other things, or even opens up the prospect of a lightweight trip to chase a sunset or something equally suitable. One potential concern that has not been an issue yet is bugs. Since I have had the bivy, the temperatures I've been out in have been rather chilly and bugs have not been out in force. While I don't think anything will work its way through the fabric and zippers, I wonder if the two inch (10 cm) opening would allow bugs in.

I would like to thank BackpackGearTest and Integral Designs for the chance to test this product.

Read more reviews of Integral Designs gear
Read more gear reviews by Louis Luangkesorn

Long Term Report

All material on this site is the exclusive property of BackpackGearTest.org.
BackpackGearTest software copyright David Anderson