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Reviews > Shelters > Tarps and Bivys > Integral Designs Penguin Bivy > Test Report by Will Rietveld

Integral Designs Penguin Reflexion Bivy

Test Series by BackpackGearTest.org

| Initial Report | Field Report | Long-Term Report |


Tester Information
Name: Will Rietveld
Age: 65
Gender: Male
Height: 6 ft (183 cm)
Weight: 170 lb (77 kg)
Email: (willi_wabbit at bresnan dot net)
City & State: Durango, CO 81301
Location for Testing: Southwestern US (Colorado, Utah, Arizona, New Mexico).

Backpacking Experience—I have been an avid backpacker for 50 years. Backpacking is my passion. I backpack the year around in the Southwestern United States (Colorado, Utah, Arizona, and New Mexico).

Backpacking Style—I have been a lightweight backpacker for 35 years and an ultralight backpacker for 9 years. My wife and I give presentations on lightweight and ultralight backpacking in our local area, and have developed a website called Southwest Ultralight Backpacking (http://home.bresnan.net/~swultralight/) to share information.


Initial Report (March 3, 2008)

Product Information (photo)
Manufacturer: Integral Designs
Manufacturer Website: http://integraldesigns.com/
Product Tested: Penguin Reflexion Bivy
Year of Manufacture: 2008
Size Tested: One size
Color: Yellow
Length and Girth: Length 84 in (213 cm), chest girth 76 in (193 cm), hip girth: 64 in (163 cm), foot girth 42 in (107 cm)
Fit Range: Fits to 6 ft 4 in (193 cm)
Packed size: 3 in x 3 in x 14 in (8 x 8 x 36 cm)
Weight: Measured weight 22.3 oz (632 g); manufacturer weight 23 oz (650 g)
MSRP: $265 US

The Integral Designs Penguin Reflexion Bivy is made of SympaTex Reflexion fabric, which has a thin aluminum layer (bonded to its membrane) that is claimed to reflect back 75% of body heat. (Photo from Integral Designs website.)
The Integral Designs Penguin Reflexion Bivy is made of SympaTex Reflexion fabric, which has a thin aluminum layer (bonded to its membrane) that is claimed to reflect back 75% of body heat. (Photo from Integral Designs website.)

Product Description
What is unique about the Integral Designs Penguin Reflexion Bivy is that it is made entirely of SympaTex Reflexion, a waterproof-breathable 3-layer fabric that contains a thin aluminum layer that reflects body heat back to the sleeper. The bivy is claimed to add dramatically to the warmth of a sleeping system. According to the fabric manufacturer (SympaTex), the Reflexion fabric reflects as much as 75% of infrared rays (heat that the body gives off)  back to the body. Because of its heat retaining technology, the Penguin Reflexion Bivy is intended for winter and high altitude use, and for use as a rescue bivy.

The Penguin is designed as a standard bivy; it does not use any poles or hoops to hold the bivy above the face. Rather it has a stiffened shape to lift the bivy above the sleeper's face. 


Features (Compiled from the Integral Designs website and hang tags on the bivy)

  • 3-layer SympaTex Reflexion fabric has a waterproof/breathable inner membrane with a thin aluminum coating that reflects back body heat
  • All seams are seam taped on the inside
  • Top center ˝ length (48 in/122 cm) waterproof zipper with three sliders
  • Stiffened face vent keeps fabric away from the face
  • Tunnel vent behind the head
  • Two stake loops at top corners
  • Silnylon stuff sack

Initial Impressions
The Penguin is a serious mountaineering bivy constructed of a durable 3-layer (face fabric, membrane, lining fabric) waterproof/breathable fabric (SympaTex Reflexion) that has the unique characteristic of reflecting back body heat to keep a sleeper warmer. 

I did some internet research for a description of SympaTex Reflexion fabric, and found some good information in the Wikipedia. The unique heat reflecting technology in Reflexion fabric is accomplished by condensing aluminum vapor on the the fabric's membrane, creating an aluminum layer only a few micrometers thick sandwiched between its membrane and lining fabric, which reflects much of the radiated heat from the human body to preserve the user’s warmth. 

The SympaTex membrane is made of a hydrophilic polyether-ester copolymer, which has no pores, and can be referred to as a monolithic membrane. It functions similar to the common polyurethane membrane, i.e. no water can get in from the outside, but water vapor transport from the inside to the outside through the membrane is by way of an absorption and evaporation processes (vapor to liquid to vapor) . This sluggish moisture transfer through the membrane is what is referred to as "breatheability". A closed membrane like SympaTex is much less efficient compared to microporous membranes (such as eVENT) which have microscopic pores that let air and water vapor pass through, yet have such low surface energy that the surface tension of any liquid water in contact remains too high to allow it to squeeze through the pores.

Interestingly, there are no instructions included on how to best use the bivy, other than to use the bivy on top of a pad to protect the fabric and to leave an opening in the zipper to ensure proper ventilation. I presume that the user would want to breathe outside air through a breathing hole in the zipper, rather than exhale into the bivy, which would cause carbon dioxide and moisture buildup inside the bivy. The purpose of the tunnel vent behind the head is not stated, but it’s apparently provided to ensure an air supply should the user decide to breathe inside the bivy.

Assessment So Far
Materials and Construction— Although the weight of the SympaTex Reflexion fabric is not provided, it is about the same as a typical 3-layer eVENT or Gore-Tex fabric used in shell jackets, which is around 2.5 oz/yd2 (85 g/m2). A 3-layer fabric is a sandwich of a face fabric, membrane, and inner lining.

While the Penguin Reflexion Bivy is not ultralight at 22.3 ounces (632 g), it is not as heavy as some bivys that include poles to expand the head area. To raise the bivy above the face, the Penguin incorporates panels of shaped stiffer fabric that expand the bivy out so the fabric does not lie on the sleeper’s face. Its waterproof zipper has three sliders so a breathing hole can be placed in the desired spot.

The bivy’s construction is excellent, with even tight stitching throughout and neat taping of all seams on the inside.

Size and Fit—The Penguin bivy is over-sized so it will fit over virtually any sleeping bag. The chest girth is 76 in (193 cm), which is about 10-12 in (25-31 cm) more than the girth of a typical 10-15 F (-12 to -9 C) sleeping bag. I inserted a size long down sleeping bag rated at -10 F (-23 C) into the bivy and it accommodated it with a little room to spare. From this I conclude that the Penguin is sized so it will fit over a size long sleeping bag rated for extremely cold temperatures (-20 F/-29 C or below) without compressing the down.

Field Report (May 13, 2008)

Amount of Use
During the first two months of testing I slept in the Penguin Bivy on five trips totaling 13 nights, summarized as follows:

Type of Trip

Number of Trips

Number of Nights

Winter Camp in Igloo

2

10

Winter Camp in Tent

2

2

Winter Camp in Open

1

1

Totals

5

13


Type of Use
Shortly after receiving the Penguin Bivy for testing, I took it on two igloo camping trips. The first was for two nights in an igloo I built in our local mountains at 9500 ft (2896 m) elevation, where the low temperature inside the igloo was 28 F (-2 C) and outside temperatures were near 0 F (-18 C). The second was a nine day trip in Yellowstone National Park, Wyoming, where we established three different igloo base camps and slept in igloos eight nights. Low temperatures inside the igloos ranged from 18 F to 25 F (-8 to -4 C), while outside temperatures ranged from -16 F to 4 F (-27 to -16 C).

I also did three overnight winter camping trips in our local southwest Colorado Mountains. The first was in a double wall tent where the overnight low temperature got down to 16 F (-9 C), the second trip was in a single wall tent where the overnight low was 17 F (-8 C), and on the third trip I slept in the open (no tent) where the overnight low was 20 F (-7 C) and breezy.

With two people in a double wall tent, I stayed warm while sleeping in a 20 F (-4 C) rated sleeping bag and the Penguin Bivy on a 16 F (-9 C) night.
With two people in a double wall tent, I stayed warm while sleeping in a 20 F (-4 C) rated sleeping bag and the Penguin Bivy on a 16 F (-9 C) night.

On the igloo trips I slept in a 15 F (-9 C) rated synthetic sleeping bag with a full-length zipper on the left side, and on the remaining trips I slept in a 20 F (-7 C) rated down sleeping bag (GoLite Adrenaline 20, which I am also testing) with a half-length top zipper. On all trips I slept on a thin inflatable sleeping pad on top of a closed-cell foam sleeping pad. The pads were under the bivy, not inside it.

Sleeping in the Integral Designs Penguin Reflexion Bivy inside a double wall tent.
Sleeping in the Integral Designs Penguin Reflexion Bivy inside a double wall tent.

Performance
Fit and Roominess—The Penguin Bivy has plenty of room inside for the 15 F (-9 C) synthetic and 20 F (-7 C) down sleeping bags I used in my testing. It has lots of girth at the head end and much less girth at the foot end, with roughly the same proportions as my sleeping bags. I inserted a 0 F (-18 C) down sleeping bag inside the bivy to see how it fits, and found it comes close to filling up the bivy, especially at the foot end. I suspect that a sub-zero sleeping bag would be a tighter fit.

With the sleeping bags I used, I found the Penguin Bivy to be plenty roomy inside. There was ample room to store items between my sleeping bag and the bivy to keep them warm, and to reach out of my bag to place them in the right location. My process for getting settled at night was to zip the bivy from inside to get my breathing hole in the right location, zip up my sleeping bag to line up with the breathing hole, and adjust the bivy opening if necessary.

Warmth and Comfort—While there is no easy way for a tester to actually measure the gain in warmth from using a bivy, my estimate is about a 5 to 10 degree F gain (3-6 degree C) from the Penguin Bivy.  Its SympaTex Reflexion fabric does seem to make some difference in warmth. On nights where the air temperature was challenging the temperature rating of my sleeping bag, I was toasty warm inside the Penguin Bivy, although I was wearing lots of clothes inside my sleeping bag just to make sure.

Features—The Penguin Bivy has three sliders on its half-length top zipper that allow positioning a breathing hole in the right place, plus an extra opening for ventilation if desired. That feature worked very well for me.

Another feature of the bivy is its stiffened shape in the head area to keep the fabric above my face. I could not put that feature to use because I did not want to zip myself entirely inside the bivy, and rely on an air supply only through the vent at the top of the bivy. That would put a lot of moisture from my breathing inside the bivy and would be very claustrophobic. Instead, I kept an opening in the zipper that I could breathe through, as shown in the photo above. On really cold nights my face got a bit cold using that technique, so I had to close down the size of the opening. When using a breathing hole, the stiffened fabric was more of a hindrance than a help, because it made it harder to place the breathing hole right at my mouth so I exhaled outside the bivy.

I also found that the Penguin Bivy’s top half-length zipper works best with a sleeping bag with the same zipper location. I used the bivy with a sleeping bag with a left side zipper and found it to be significantly less convenient compared to a top zippered bag, such as the GoLite Adrenaline 20 that I am also testing.

Breathability—The waterproof-breathable SympaTex Reflexion fabric used in the Penguin Bivy functions similar to a polyurethane laminate (not very breathable), so I was concerned about condensation inside the bivy.  On nights that I slept in igloos I had only minor condensation inside the bivy. However on two of my other trips, in colder temperatures, I had abundant condensation (frost) on the inside of the bivy. This occurred on a still 16 F (-9 C) night while sleeping in a two-person double wall tent on top of a 10 ft  (3.1 m) deep snowpack, and on a breezy 20 F (-7 C) night while sleeping under the stars, also on snow.

Condensation (frost) inside the Penguin Bivy after sleeping under the stars on a 20 F (-7 C) night.
Condensation (frost) inside the Penguin Bivy after sleeping under the stars on a 20 F (-7 C) night.

One fear I had on my extended igloo trip was moisture accumulation in my sleeping bag. However, I didn’t have any problem at all. I hung my synthetic sleeping bag on a clothes line every day or two just to make sure it stayed dry. Inside the igloo, I kept the bivy around my sleeping bag all the time to prevent any moisture from getting into my sleeping bag from the outside.

Durability and Packability—The entire bivy is constructed of the SympaTex Reflexion fabric, which has a durable nylon face. After two months of use there are no signs of wear. However, at 22.3 ounces (632 g), the Penguin Bivy is no lightweight. I would personally be reluctant to carry it in a backpack and use it in combination with another shelter. Rather, I would be more inclined to use it by itself as my primary shelter, perhaps with a small tarp over the head area in the event of rain.

Long-Term Report (July 16, 2008)

Amount and Type of Use
After my Field Report on May 10, I had little time left to test the Penguin Bivy under really cold conditions. I did one more snow camping trip in mid May where I backpacked to 11,700 ft (4566 m) and slept overnight without a shelter, on top of an 8 ft (2.4 m) snowpack. The nighttime temperature only got down to freezing (32 F/0 C), but a strong convectional breeze kept up all night. I slept in a 20 F (-7 C) rated sleeping bag (GoLite Adrenaline 20) with a center half zipper.

Morning after a night spent sleeping under the stars in the Integral Designs Penguin Reflexion Bivy.
Morning after a night spent sleeping under the stars in the Integral Designs Penguin Reflexion Bivy.

Additional Comments
I have very little to add to my comments in my Field Report. On the one additional trip described above, I did not find any condensation inside the bivy the next morning. I estimate that the bivy added about 10 degrees F (5.6 degrees C) to the overall warmth of my sleeping system, in part by greatly reducing convective heat loss when I slept in the open.

Overall Assessment
The unique feature of the Integral Designs Penguin Reflexion Bivy is its use of SympaTex Reflexion fabric, which contains a thin aluminum layer to reflect back and conserve body heat. My impression based on my testing is that the bivy adds about 10 degrees F (5.6 degrees C) of warmth to a sleeping system, depending on the conditions. Although I have no means to measure the fabric’s breathability, I note that I had few problems with condensation inside the bivy. The only instances of condensation I encountered were after very cold nights, where I found quite a bit of frost on the inside surface of the bivy. The bivy is well designed and constructed, and is sized to fit over a sub-zero rated sleeping bag. At 22.3 ounces (632 g), the Penguin Bivy is an average weight for a bivy made of heavier, more durable fabric.

Acknowledgement
I would like to thank Integral Designs and the BackpackGearTest Group for selecting me to participate in this test.

Will Rietveld



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Reviews > Shelters > Tarps and Bivys > Integral Designs Penguin Bivy > Test Report by Will Rietveld



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