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Reviews > Shelters > Tarps and Bivys > Integral Designs eVENT Crysallis Bivy > Gail Staisil > Test Report by Gail Staisil

Integral Designs Crysallis Bivy
Test Series by: Gail Staisil, Marquette, Michigan

Initial Report:
Integral Designs Crysallis Bivy
January 23, 2007

Tester Information

Gail Staisil
Age: 54
Gender: Female
Height: 5' 9" (1.75 m)
Weight: 140 lb (64 kg)
Location: Marquette, Michigan USA

For the last 17 years, backpacking has become a passion. I am a four-season backpacker and an off-trail navigator. Although I do take yearly trips to the American West or Southwest, the majority of my trips are in Michigan and Canada. My pack weight varies considerably but my base weight is below 18 lb (8 kg). I am primarily a tarp camper who averages more than 50 nights a year backpacking in a huge variety of weather conditions including relentless rain, wet snow and sub-zero temps.

Product Description

Integral Designs
Phone 1.403.640.1445
Model Crysallis
Dark Green and Black
90 in (229 cm)
30 in (76 cm) at shoulders, tapers to 22 in (56 cm) at foot
74 in (188 cm) at shoulders, tapers to 52 in (132 cm) at foot
Packed Size
Length 8 in (20 cm), Diameter 5 in (13 cm)
Weight (Manufacturers)
1.80 lb (810 g)
Weight (Testers)
1.55 lb (703 g)
eVENT (60 percent), nylon (40 percent)
Model Year 2007
Country of Manufacturer
Canada (Calgary, Alberta)
MSRP $255.00 US

The Crysallis Bivy is one of many bivy selections that is made and offered by Integral Designs. It belongs to their "fast and light" gear system series. According to the manufacturer the line is "designed for self-propelled adventurers doing short duration trips into the outdoors". The Crysallis features a wire-stiffened dome shape over the head area, a rear facing tunnel vent in the hood, a continuous zipper with two sliders that allows the top to be unzipped to the waist on both sides, and no-see-um netting. The Crysallis comes in one size that can reportedly accommodate sleepers up to 79 in (201 cm).

All Integral products are warrantied to the original owner against defects and workmanship. If a product fails due to manufacturing defect, Integral will repair or replace it at its option. Repairs due to accident, improper use, or wear and tear will be charged on a time and material basis.

Initial Impressions Crysallis Bivy in stuff sack
The Integral Designs Crysallis Bivy arrived in perfect condition. The bivy was encased in a small stuff sack measuring approximately 8 in (20 cm) in length and 5 in (13 cm) in diameter. A small tube of SEAMGRIP and accompanying instructions for its use was included. It was written in both English and French. The manufacturer suggested applying the SEAMGRIP product to insure maximum waterproofness to areas where factory-taped seams weren't present, or on the top of seams where two different types of materials were seam taped together. For example, the floor of the bivy is made out of polyurethane whereas the top of the bivy is made out of eVENT fabric.  

The Crysallis Bivy looked very much like it did on the website as far as the design and the color (dark green). Even though I had studied the measurements of the bivy, I was delighted to find that it seemed roomier than I expected. I own a couple of other bivies but only one of them is a commercial item and it is very constricting so I never use it anymore. My other bivies were made by me and they are simple in design and roomy. My preference is for the latter quality, so I was very impressed by the size of the Crysallis Bivy.

I immediately took out my -20 F (-29 C) degree down sleeping bag and put it inside the unzipped bivy and then I crawled into it to assess its attributes. I didn't find any areas of restriction where it would compress my sleeping bag or lay tightly against my body. In fact, I can move both of my arms quite freely within the bivy to adjust the two-way zippers, the wire-stiffened dome and the back vent. Although I didn't feel claustrophobic, I did wonder if it would bother me to not be able to see outside of the bivy with the zipper in the closed position. I should relate that all of my other bivies are of the simple envelope type where the overlapped opening is across the top of the chest making it easy to see outside if necessary. I guess testing experience will determine if this bothers me in the long term.

The Crysallis Bivy is made out of two types of fabric. The bottom of the bivy is made out of waterproof or coated nylon. The top and sides of the bivy are made out of eVENT waterproof fabric. The material has a very silky and crisp feel to it. According to the manufacturer, eVENT Fabric is a "Direct Venting", air-permeable PTFE trilaminate fabric with a triple grid 30 denier nylon face fabric. Condensation is supposed to dissipate and vent before saturating the inside of the fabric. The core of the fabric is designed to repel body-oil contamination. The instruction sheet that came along with the SEAMSEAL did relay to expect some condensation in warm and humid conditions.

All of the major seams in the bivy are nicely sewn and completely finished with seam tape. The only exceptions are the areas where the zippers are inserted and the bottom edge of the tunnel vent. However, the outside zipper is water-resistant and Two-way zipperthe bottom edge of the vent is not directly inside of the bivy making seam taping unnecessary.

The bivy has a tapered shape from top to bottom with the greatest width being at the shoulders. The bottom edge of the bivy is shaped to accommodate the height of a sleeping bag and is of three-dimensional design.  A long continuous zipper with two sliders is inserted into the sides and the eVENT top of the bivy. The zipper is water-resistant and is placed into the bivy starting on one side at waist height, then circles the back of the head area and stops at the waist height on the other side. The zipper measures approximately 83 in (211 cm) in length. This adds a great deal of versatility to enter and exit the bivy as well as to adjust air flow.

No-see-um mesh insert

The Crysallis Bivy has an inner insert of no-see-um mesh that is sewn into the bivy. It begins at the waist and ends at the top of the bivy. This insert can be tied in place at the waist position so that it is out of the way during cold or wet usage. The insert has its own set of two-way zippers for closure of the bivy. There is a simple braided flat cord inserted into the center seam on both sides of the mesh so that it can be gathered and secured if it is not being used. There is also a cord attached to the center top waist seam for the same purpose if I want to use the mesh section rather than the eVENT top portion.

The construction of the mesh pieces are dome shaped and they are encased in grosgrain ribbon. There is a also a short piece of braided cord sewn at the height of the mesh that can presumably be used to tie it out of the way as it doesn't have a wire stiffener to hold it away from my face. I will most likely attach a longer piece of cord to it, so that I can pull it out to a tree branch to keep the mesh off my face. The mesh insert has a tag inserted into the seam that states a suffocative warning. It says: "Always leave zipper open at least 6 inches (15 cm) to allow air to enter."  I'm sure that by industry safety standards it must be suggested, but a 6 in (15 cm) opening seems like it would be a welcome center for bugs to enter during spring weather.

The dome-shaped head area of the eVENT Fabric is supported by a single thin white flexible rod that is encased in fabric. There is also a rear-facing back vent that is very innovative. It is circular in shape (approximately a 5 in (13 cm) diameter) and it tapers or funnels to a narrower diameter of 4 in (10 cm) and it is about  6 in (15 cm) long at the top and 2 in (5 cm) at the bottom. The tunnel is sewn into the bivy at a downward angle so that it doesn't catch precipitation. It can be totally closed with a cordlock or adjusted to various positions in between. There is a loop sewn on the top edge of the vent to allow it to be tied off to a tree branch or similar.Closed tunnel vent
Wire-stiffened dome

In the next four months, I will have ample opportunity to test the Crysallis Bivy in both winter and early spring conditions on many extended backpacking trips. There should be plenty of precipitation in the form of snow, sleet or rain and the nighttime low temperatures could range from a low of -40 F (-40 C) in February to a low of 39 F (4 C) in May. Testing locations include deciduous and pine forest, open plains, frozen lakes, lakeshore and steep rocky trails. The testing conditions are at low elevation or altitude 600 ft (183 m) to 2000 ft (610 m).

  Crysallis Bivy
  • Roomy
  • Easy access to enter or exit
  • Water-resistant zippers
  • No-see-um netting allows its use for all seasons


  • Can't see outside the bivy when the zipper is fully closed

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Field Report:
Integral Designs Crysallis Bivy
April 18, 2007

Locations and Conditions

During the field test period of almost three months, I have used the Integral Designs Crysallis Bivy during many multi-day adventures. They included a solo three-day winter sledge trip to Pictured Rocks National Lakeshore in February, a four-day winter sledge trip also to Pictured Rocks in March and a four-day backpacking trip to the Pigeon River State Forest in early April. All trips were located in the Upper and Lower Peninsulas of Michigan. Locations ranged from and included conifer and deciduous forest communities with many rock outcroppings to plains, frozen lakes and lakeshore. Elevation ranged from 600 ft (183 m) to almost 2000 ft (610 m).

Trip # 1: Conditions for the first sledge trip lasting three days were cold, cloudy, blustery and extremely windy. High temperature was 18 F (-8 C) and the low temperature was -4 F (-20 C). Brutal northwest winds with gusts up to 45 mph (72 km/h) were experienced with the average wind speed being 30 mph (48 km/h). Snow depth ranged from about 16 in (41 cm) near the lakeshore to well over 24 (61 cm) to 30 in
(76 cm) inland. There was also significant drifting of snow making travel harsh. 

Trip # 2: The second sledge trip had conditions over a four day period that were moderate in temperature (18 F/-8 C to 30 F/-1 C) but much precipitation occurred during the second and third day of the trip. Approximately 15 in (38 cm) to16 in (41 cm) of very wet snow fell making travel difficult. Wind speeds of over 30 mph (48 km/h) were experienced. Snow depth was several feet (3 ft/1 m).

Trip # 3: 
The weather for the four-day Pigeon River State Forest trip was mostly cloudy and damp with episodes of rain each day and night. Total precipitation was approximately 0.50 in (1.3 cm). Temperatures were mostly in the 40 F to 45 F (4 C to 7 C) range with a high of nearly 60 F (16 C) and a low of approximately 28 F (-2 C).

Performance in the Field

Ease of Use/Comfort

My first experience with the Crysallis Bivy took place on a solo trip during frigid or below zero (0 F/-18 C) temperatures. Because high winds were a factor, I set up a 10 ft (3 m) X 10 ft (3 m) silnylon tarp over the area where I would sleep. After I arranged the bivy, I adjusted the wire-stiffened dome and I then opened the two-slider zipper on the bivy to insert my sleeping bag. The interior of the bivy is so accessible with this neat zipper configuration that zips entirely from waist height upwards and around down to waist height again. The water-resistant zipper is a bit stiff to operate with gloved hands, but I later opened it while being half asleep so it's not much of an issue. It was great to not have to wrestle with the insertion of an overstuffed sleeping bag. I have previously used only bivies that have a small envelope opening across the chest area and it was often a struggle to insert and remove the sleeping bag, let alone me. The Crysallis is nice and roomy both length and width wise measuring a maximum of 74 in (188 cm) of girth at the chest and my -20 F (-29 C) down sleeping bag fits in it with much room to spare. I have also stored other items outside of the perimeter of my sleeping bag including a couple of padded water bottle cases and my mukluks that were inside a large silnylon sack.

After I slipped into the sleeping bag and laid down to rest, I pulled the bivy's zipper ends to about 6 in (15 cm) apart. I did this both for a bit of fresh air and to abate any possible claustrophobic feelings as the bivy covers any direct visibility to the outside. I then partially zipped up my sleeping bag as there was plenty of room to extend my arms inside the bivy to do whatever task I needed to accomplish. The wire-stiffened dome area of the bivy is really quite spacious and I hadn't any difficulty with it touching my face even when I turned from side to side. During the entire night, 45 mph (72 km/h) winds were knocking humongous mounds of heavy snow off of the hemlock trees that were predominant at my camp site. I was glad that they were hitting the tarp rather than the bivy as the weighty chunks could easily have knocked me out. I settled into sleep only to be reawakened repeatedly by the snow assault. Anyway, I was pleasantly surprised that the bivy was so comfortable and blocked the significant wind chill and cold. In fact, I initially had the zipper open maybe 6 in (15 cm) but found that I had to open it to twice that length as I was quite warm. Inside the bivy I was partially encased in my -20 F (-29 C) sleeping bag. I didn't have the draft collar secure and my wool-hat clad head was lying on top of the hood. It didn't seem possible that it was actually -4 F (-20 C) outside. I really liked this arrangement and I can only speculate that the added protection of the bivy has made sleeping warm possible without being totally encased in my sleeping bag (I am by nature a cold sleeper).


The next night I also used the tarp with the bivy. Wind and lake-effect snow were prevalent. I was again pleased with the performance and comfort. Inside the bivy only the slightest bit of frost was evident on the upper portion of my sleeping bag whereas the inner portion of the bivy felt dry to the touch.
Bivy in open-sided shelter
During the second trip, a severe winter storm was in effect. I again slept in the bivy with the protection of a tarp overhead. Even with sufficient anchoring the tarp bowed greatly during the night due to more than a foot (30.5) of wet snow that fell in a short period of time. The bivy did get partially snow covered but the snow was easy to shake off in the morning. The second night of the trip the snow storm still prevailed and the winds increased. I had a combination shelter of sorts with my tarp set up in an explorer-type configuration with three-quarter snow walls completing the other two sides. I was a bit colder that night even with all the protection provided by the enclosed space. After closing the bivy zipper all the way I became warmer. I was certainly glad to have the bivy to add more protection from the wind chill that was drifting in through the doorway of my mostly snow-enclosed tarp.

The third night was a bit calmer, but the winds were still strong. I kept the zipper open a short distance on the side where I faced. When I switched sides during the night I moved the zipper opening to the other side. It allowed me to see out a bit and also to breathe fresh air. The rear facing tunnel also provides those attributes so if I crank my head back I can actually see outside of it. (Although I don't really feel claustrophobic in the bivy, I still like to see outside when I wake up.) The tunnel provides great ventilation too and is most likely part of the reason that there has been little-to-no moisture build-up inside of the bivy. The fabric face of the inner side of the bivy is very comfortable to touch and handle.
The eVENT fabric has performed well in very cold weather and it didn't change or stiffen so it was easy to pack after each night's camp.

The third trip took place in early spring. The snow had melted and the earth had thawed leaving a very wet ground and wet vegetation. In addition, many episodes of heavy rain during the trip added to the dampness. I slept under a smaller tarp that measured 9 ft (2.75 cm) X 9 ft (2.75 cm). Because of the uneven ground (bushwhack trip, no tent pads), I sometimes confidently slept with the lower portion of the bivy outside of the actual tarp coverage. Those areas experienced rain and wind but were not affected due to the waterproof nature of the bivy. Beads of water on the outside were quickly shaken off before I packed the bivy in my pack. No hint of saturation of fabric occurred.

Overall, even with the very high humidity on several of these trips (upward to 100 percent), there has been essentially very little perceptible moisture build-up in the bivy. My sleeping bag of choice on each of the trips has stayed completely dry including my -20 F (-29 C) down bag on the winter trips and a 20 F (-7 C) synthetic bag on the spring trip. The eVENT fabric of the bivy is seemingly more breathable than any of the other bivies that I have used that also were made of highly technical (but different) fabrics. 

During all of the trips, I used the bivy in combination with the POE Hyper High Mtn Mat that I'm also testing. The bivy was directly placed on top of the mat during the first two trips and the mat was inserted inside of the bivy on some nights of the last trip. There is plenty of room inside the bivy to accommodate this thick mat (1.5 in/3.8 cm thick). I'm not sure which method of placement I really prefer, but without using a ground cloth for protection I lean more towards having the mat underneath the bivy to protect the bottom of the bivy from sharp rocks and thorny vegetation.

So far I haven't had to do any maintenance to the bivy. The fabric, seams, and zippers are in perfect shape and there isn't any hint of a need for washing it. In the long term period, the bivy will be tested without the additional use of a tarp on some trips and I'm looking forward to using the bug netting option. Late spring conditions will certainly warrant that. Durability issues and warm weather comfort will be addressed.


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Long Term Report:
Integral Designs Crysallis Bivy
June 12, 2007

Locations and Conditions

During the long term testing period, I have used the Integral Designs Crysallis Bivy for three more multi-day backpacking trips. Additional days in the field amounted to twelve. Locations ranged from and included conifer and deciduous forest communities with many rock outcroppings to sand dunes, lakeshore and swamps. Elevation ranged from 600 ft (183 m) to almost 2000 ft (610 m).


Trip # 4: 

Location: North Country Trail - Lower Peninsula of Michigan
Type of Trip: Trail (maintained), moderate terrain
Distance: 36 mi (58 km)
Length of Trip: 4 days
Pack Load: 25.5 lb (11.5 kg)
Sky and Air conditions: Cloudy, sunny, low-mid range humidity
Precipitation: Trace
Temperature Range: 36 F (2 C) to 66 F (19 C)

Trip # 5: 

Location: North Country Trail - Western Upper Peninsula of Michigan
Type of Trip: Rugged unmaintained trail section (several hundred blowdowns, washed out bridges), wide river crossings, severe terrain
Distance: 54 mi (87 km)
Length of Trip: 6 days
Pack load: 30 lb (13.6 kg) to 40 lb (18 kg) when hauling extra water for dry bivouac sites
Sky and Air conditions: Mostly cloudy, rain and sun, mid-high humidity
Precipitation: (Rain) 0.69 in (1.75 cm)
Temperature Range: 34 F (1 C) to 86 F (30 C)

Trip # 6: 

Location: Pictured Rocks National Lakeshore
Type of Trip: Trail
Distance: 17 mi (27 km)
Length of Trip: 2 days
Pack load: 21 lb (9.5 kg) 
Sky and Air conditions:
Sunny, windy, cloudy, mid-range humidity 
Precipitation:  None
Temperature Range: 39 F (4 C) to 66 F (19 C)

Performance in the Field

Bug Netting

The Integral Designs Crysallis Bivy has continued to perform well in the long term period. It was subjected to far different conditions than in the field test period. With the advent of spring, the bug netting has become an absolute necessity. Even though the average nighttime temperatures have been approximately 35 F (-2 C) at the minimum, the netting was more important in the earlier and warmer hours of the evening. When I went to bed the bugs were still highly active (about 60 F/16 C). Black flies and mosquitoes were the main nuisances. I normally completely zipped up the inner mesh netting of the bivy using the two-way zipper and then partially zipped the outer eVENT layer.
I often had to do all of this quickly as I didn't want to let any bugs into the bivy. During most nights, I remained quite comfortable with this arrangement so I didn't need to completely zip the outer layer later.

The bug netting has an unwired shaped-dome area that lies over my head. Most nights I just pushed it away from my face and it stayed adequately in place until I shifted into another position (side sleeper). I would repeat the procedure and I was good for another couple of hours. I also tried the alternative of fastening a long piece of cord to the short length of tie that is inserted into the contoured seam above the head. I used it to pull the entire mesh section away from my head. This worked perfectly when attached to a tree branch or similar. This is perhaps the preferred method for dealing with a heavy invasion of mosquitoes as they can drill away but not have contact with their human target - me.

Although I didn't have to use the wire-stiffened dome portion of the eVENT layer during the long term period, it saw constant use during the field period. I'm only mentioning this because every time the complete bivy is stuffed into the storage sack, the wire has to be reshaped so that the dome area can function well. I also reshaped the wire during the long term period each time I took it out of the stuff sack. I wanted it to be ready in case I needed to zip up that portion during the middle of the night. All of this bending hasn't affected the wire in anyway and it is still encased nicely in the casing.

Comfort/ Waterproofness

It rained on several occasions while using the bivy. Although I was sometimes partially protected by a tarp, the bivy was also subject to blowing rain for several hours and wet ground. I didn't find any evidence of water leakage through the fabric, zippers or seams during the test period.

I have been perfectly content with the breathability and comfort of the bivy. Even though it has been subject to very high humidity (up to 100 percent) and moderately high temperatures (60 F/16 C to 75 F/24 C) a few times, I'm amazed that the fabric didn't make me feel too warm. Only the upper portion of the mesh netting was used when these conditions occurred, but my lower body was still encased in both the eVENT fabric shell and a partially zipped sleeping bag. My sleeping bag never felt wet when I pulled it out of the bivy each morning. Condensation was never a problem as the inner layer of the bivy also felt dry. I can only surmise that moisture vapor vented out of the breathable fabric perfectly.


I haven't felt the need to do any real maintenance to the bivy. The fabric, taped seams, wire dome, mesh netting and zippers remain in perfect working order. The bivy can be hand washed with mild soap and then let to drip dry. I will do that in the future when it needs it. I have primarily used the bivy with a sleeping pad underneath it, so the bivy has been subjected to little in the way of dirt or vegetation. However, all edges of the bivy did extend over the edges of the pad as it is simply longer and wider than the pad. My only gripe would be that the bivy is hard to stuff into the small provided sack. I will be using a bigger sack for convenience sake after the testing period is completed.

To summarize in brief, I am very impressed with the Integral Designs Crysallis Bivy. Although I own several bivies which include a commercial bivy and two homemade bivies, the Crysallis Bivy features all of their best attributes together. Its roominess, breathability, watertightness, easy access and versatility are topnotch. During the entire testing period, the bivy was used from temperatures that ranged from -4 F (-20 C) to 75 F (24 C) at night. It was used during snowstorms, rainstorms and high humidity temperatures. It accommodated sleeping bags rated from -20 F (-20 C) to 25 F (-4 C) and I found it roomy enough to not feel restricted in my movement or claustrophobic in anyway. It was highly versatile for all of these conditions and I wouldn't hesitate to take it on my future trips during any season of the year. 

This concludes my test series for the Crysallis Bivy. Thanks to Integral Designs and BackpackGearTest for this great opportunity to test the Crysallis Bivy.

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