Reviews > Shelters > Tarps and Bivys > Integral Designs South Col Bivy > Jim Sabiston > Initial Report

Initial Report - Integral Designs eVENT South Col Bivy

Date: November 4th, 2003

Reviewer Information

Name: Jim Sabiston
Age: 49
Gender: Male
Height: 6' 3" (1.9 m)
Weight: 207 lb (94 k)
Girth : 52” (132 cm)
Width : 21” (53 cm)
Email address: JimSabis(at)aol(dot)com
State: New York
Country: USA

Backpacking Background:

I've been camping for several decades. I joined the Adirondack Mountain Club three years ago, the Appalachian Mountain Club a year later and am active in both. I have also expanded my backpacking to include more winter trips, mountaineering and backcountry cross country skiing, and participated in the AMC's Winter Mountaineering training program with Chauvin International Climbing Guides. More recently, I have actively studied ways to backpack lighter and more efficiently. During the summer months, my style tends toward very light, but not quite ultralight. I use a hammock or tarp for warm weather, and a small four-season tent for winter trips. Most of my other gear is very changeable, as I am constantly experimenting with gear and techniques.

Product Information:

Manufacturer: Integral Designs
Year of Manufacture: 2003
URL: www.integraldesigns.com
Size: Long
Zipper: Left handed
Color: Yellow

Manufacturers Specifications:

Length: 92 in (2.34 m)
Width: 32 in (.81 m)
Girth: Shoulders: 69 in (1.75 m)
Foot: 22 in (.56 m)
Weight (size Long): 22 oz (624 g)
Pack Size: 8 in X 5 in (20 cm X 13 cm)
Price: $245 US

Specifications as delivered:
Length: 92 in (2.34 m)
Width: 32 in (.81 m)
Girth: Shoulders :70 in (1.78 m)
Foot: 24 in (.61 m)
Weight: Bivy= 22.5 oz (638 g)
Stuff sack=.75 oz (21 g)
Pack Size: 9 in X 5 in (23 cm X 13 cm)

A note regarding measurements: Determining the precise dimensions of a fabric structure can be difficult. Soft fabrics constantly move and shift as they are measured and pulled. With this in mind, I found the dimensions provided by Integral Designs to be quite accurate.

Description of the Integral Designs eVENT South Col Bivy:

The bivy arrived in a small brown box, which was surprisingly light. Opening the box, I found the bivy packed into its stuff sack, accompanied by an Integral Designs catalog.

The Integral Designs eVENT South Col Bivy is a light-weight bivy shelter intended for year-round use. The frills have been kept to a minimum to achieve the lightest possible weight. The bivy is constructed using Integral Designs' eVENT fabric throughout the upper, exposed panels. A proprietary fabric design, eVENT is described as an improvement over the standard waterproof/breathable polytetraflouroethylene laminated fabrics (Gore-tex being the best known). Information available on the Integral Designs web site explains that the Dry System Technology, as Integral Designs refers to it, permits the elimination of a layer of polyurethane in the fabric laminate. The reported result is a fabric laminate that is lighter and more breathable, but remains waterproof. The eVENT sections of the bivy are a bright, colorful, golden yellow. The bottom of the bivy is made with a black, lightweight, urethane coated nylon. The bottom of the bivy wraps up to meet the top panels, so all seams are above ground level. All seams are finished with waterproof seam tape.

There are two zippers, one 23 inch (58 cm) black waterproof type, located on the left side per my request, and a second zipper which runs across the upper body of the bivy. Integral Designs offers the bivy with the side zipper on either the right or left side, allowing the bivy zipper to line up with my sleeping bag zipper. The upper zipper has three metal sliders which allow for a variety of venting positions. This zipper is not waterproof. As this zipper is intended to be kept open at least six inches (15 cm) to ensure sufficient ventilation, a waterproof zipper would serve no purpose. The top zipper opening is offered some protection by a six inch (15 cm) extension of the eVENT fabric which forms a brim, not unlike a very large baseball cap.

In an effort to provide some space over the bivy occupant's face, Integral Designs has built in a wire hoop in the hood area. The wire is located inside a narrow fabric tube which runs the full width of the bivy, starting and finishing near the ends of the hood zipper. The wire itself is cut from a plastic insulated, solid core copper wire. The ends of the wire are bent back about .25 inches (6 mm) to prevent the exposed ends from chafing through the ends of the fabric tube. An opening has been built into the tube, approximately 2.5 inches (6.4 cm) from the left side end, which permits the removal of the wire. As the solid copper core will no doubt eventually fatigue and break from repeated flexing (the bivy will not fit into the stuff sack without bending the wire) this will greatly simplify the wire's replacement. I removed and replaced the wire to see how difficult it would be. It took some fussing, but was not overly difficult. I think I can say with some confidence that the wire will not fall out unintentionally.

Overall, materials and construction detailing appear to be of very good quality.

Fit:

Laying the bivy out on the floor, I inserted my full length Therm-a-Rest Ultralight Self-Inflating Sleeping Pad. The pad fit into the bivy with room to spare. Next, I slipped in my winter sleeping bag, a The North Face Superlight , a down bag rated for zero degrees F (32 C), size long. I found the easiest way to do this is to place the sleeping bag lengthwise along the top of the bivy, with both of the bivy's zippers fully opened. Then, after sliding my legs into the sleeping bag, I lift up my legs, still inside the sleeping bag, and insert everything into the bivy. There is plenty of volume in the bivy for the down sleeping bag to loft properly.

I found the best way to complete my entry into the bivy was to pull the hood of the sleeping bag over my head, thus ensuring that the bag was fully stretched out before lying down. Then, lying down, I grab the hood of the bivy and pull it over my head. At this point, it is just a matter of getting zipped in. I find that it is easiest to roll over onto my left side and close the waterproof zipper using the inner toggle. This is also a good time to zip up the sleeping bag. Rolling over onto my back, I can then adjust the hood zipper.

The hood zipper has three sliders. The first slider fully closes the face opening. The other two sliders are then used to open the zipper at various positions and opening sizes as I choose. Once inside the closed bivy, I noticed that there is a permanent opening just below the point where the two zippers meet. This opening is easy to miss, as it is hidden under the overhanging brim and well down the side of the bivy. This may be a safety vent, as it prevents the bivy from ever being completely closed. Nevertheless, Integral Designs recommends using a minimum 6 inches (15 cm) of open zipper to ensure proper ventilation. As a reminder, they have even attached a reminder tag to the outside of the face zipper.

There is plenty of room to move around inside the Integral Designs eVENT South Col Bivy. Obviously, there can’t be the same room as a tent, but the bivy is still quite comfortable. As long as the face zipper is open, I did not feel claustrophobic at all. In fact, I found the experience to be rather snug and comfortable. There is sufficient room to store various bits of gear inside, but some thought will have to be given to keeping larger bulky items outside. The wire hoop, while it does hold the hood off my face, is not stiff enough to provide any real room. I attempted to hold a book in reading position with the zipper fully closed (excepting the minimum six inch (15 cm) opening) and found that it is possible to read a book in the bivy, but it takes some fiddling. My usual habit of using a candle lantern cannot work in the bivy’s close quarters and electric lighting will be the order of the day when interior lighting is needed.

One of the most important winter camping inventions is the pee bottle. I never truly appreciated the importance of this device until the first time I had to get out of my very toasty warm sleeping bag at 2:30 one morning to relieve myself. It was minus 15 degrees F (-26 C). This experience left a very real impression, one that medical science may be able to cure someday. The most obvious symptom is the development of the ability to “hold it in” until my eyeballs are floating, rather than go outside the tent in the wee hours of a dark winter morning. Fortunately, the pee bottle makes this unnecessary. There appears to be plenty of room inside the bivy to use a pee bottle without any problems. If I have a concern about using a pee bottle in the bivy, it is simply that if I experience some, umm, spillage, it will be in very close quarters. I will have to be extra careful.

Initial Conclusions:

The Integral Designs eVENT South Col Bivy is very lightweight, packs very small and appears to be very well made. The waterproof side zipper makes the bivy very easy to get in and out of. I was concerned that the side zipper would be too short to allow easy entry and exit, but it proves to be just long enough. The bivy should prove to make an excellent primary shelter if I can adjust to not having the room of a tent. The reduction in weight and space are enormous, as compared to my usual winter shelter. My mountaineering tent weighs 7.5 pounds (3.4 kg), all up, and packs 20 in X 8 in (51 cm X 20 cm). While these figures are considered quite reasonable for a four season shelter, the bivy will save over 6 lbs (2.72 kg) of weight and take up less than a third of the volume. This is no small consideration.

I am pleased with the roominess of the bivy, but would like to see the hoop hold the face panel a bit higher. A couple of inches (5 cm) would prove sufficient. I think this would greatly improve the impression of roominess inside the bivy.

Things I like:

1 - Very small and light
2 - Appears to be of high quality materials and construction
3 - Easy entry and exit

Things I don’t Like:

1 - I would like that hoop to stand a bit higher.

Test Plan:

As the test period has commenced in the Fall season, my initial focus will be on the concerns of condensation. Condensation is potentially a very real problem in a confined shelter of any type, especially in the intermediate seasons when any interior condensation remains liquid, rather than freezing as it tends to do in the winter months. As it is recommended that you breath out of the bivy, rather than into it (note the requirement to keep the face opening open by at least six inches) this may be less of a problem, as the primary source of condensation is exhaled breath. The remaining question is to determine if the moisture produced by my body will be a problem inside the bivy. The eVENT fabric is purported to breath exceptionally well. The Integral Designs web site goes into some depth describing the mechanics of the Dry System Technology and how it differs from the ‘standard’ waterproof/breathable fabric approach. If it works as described, it may well be an impressive advance.

Once into the Winter season, condensation is probably more likely, but is usually easier to deal with in a tent, as it tends to freeze on the tent wall. A well used candle lantern will dispense with this, as will a small ‘tent broom’ or rag. Obviously, the candle option cannot apply to a bivy, so breathability will be all the more critical. Will there be any condensation build up at all? If so, will the close quarters of the bivy prevent it from freezing? This will be a very important consideration for multi-day cold weather trips.

Primary concerns are how I will adapt my equipment habits to not having a tent. Is there enough room to keep water and fuel bottles inside with me to prevent them from freezing, or will the bivy feel like an overstuffed cupboard? What other equipment can I fit inside and what will be left outside, at the mercy of the elements.

Finally, as the tent will be left behind, the bivy will be used in lean-tos, under a tarp (even in the snow), and in the open. How does that waterproof zipper hold up when pressed into snow while I am sleeping in the bivy? Other factors, such as packability and durability (especially of the lightweight, waterproof bottom) will be observed. I also look forward to the opportunity to practice and refine my Winter Mountaineering training with this bivy. One of my goals is to determine just how light I can go with my winter gear without compromising comfort and safety. The Integral Designs eVENT South Col Bivy should provide an excellent vehicle for refining my winter survival techniques.

I would like to extend my thanks to Integral Designs for the opportunity to test this very interesting product.

Reviews > Shelters > Tarps and Bivys > Integral Designs South Col Bivy > Jim Sabiston > Initial Report