Field test

Big Agnes REM Air Core mummy pad

Web site: http://www.bigagnes.com/

Tester: Mara Factor
Gender: Female
Height: 6’1"
Weight: 195
Age: 36
Test Locales: Medford, MA (north of Boston); Long Trail, VT; Trail Days in Damascus, VA; and a couple of spots along the Appalachian Trail in NY and PA.
Date: July 30, 2002
Email: m_factor@hotmail.com

Web: http://friends.backcountry.net/m_factor

Background: I have been hiking and backpacking extensively since 1989. Weekends frequently find me in the White Mountains of New Hampshire. Longer trips I've taken include (but are not limited to) such diverse locations as Copper Canyon, Mexico; Annapurnas, Nepal; Olympic Mountains, Washington; Austrian Alps; Paria Canyon, UT and AZ; and a 1999 thruhike of the Appalachian Trail.

Item(s): REM Air Core mummy pad - long

Acquired: May 2002 as an adjunct test to the ongoing Horse Thief test

Reputation: I became familiar with Big Agnes as a result of my participation on the BackpackGearTest list. Big Agnes is one of the few sleeping bag and pad manufacturers taking a lead with the concept of lightening bags by eliminating the mostly useless insulation that traditionally gets compressed under the hiker while sleeping.

Description: The Big Agnes sleep system comprises an integrated sleeping bag and pad. The mummy shaped top bag has a sleeve on the bottom to accommodate the mummy shaped pads offered by Big Agnes. Please see the Zirkel report for information on the sleeping bag.

The REM Air Core Mummy pad is a true air mattress with only enough internal structure to keep the air in six long baffled columns. Unlike self-inflating open cell foam pads, this pad requires you to blow up the pad. True to the documentation, it is easily inflated in about two minutes. Firmness is determined by how much air you blow in. Because there is no internal foam, the pad packs suprisingly small. It is shaped to exactly fit into the mummy shaped sleeve on the bottom of the Zirkel bag. Because it is essentially one large air chamber, it only provides limited insulation from the ground.

The pad came with a heavy coated nylon stuff sack and includes a repair kit.

Specifications:
Pad stuff sack with repair kit: 5 x 11", 2 oz.
Pad: 1 lb 6.5 oz., from web site, 1 lb 6 oz.
Pad: 2.5" x 20" x 78" once inflated

Fit: While many lightweight backpackers tend to go with short sleeping pads to save weight, given the integrated nature of the bag and the pad, it is necessary that the matching pad and bag be used to optimize performance.

The 78" long pad is generously cut for my frame and could easily accommodate taller and/or larger people.

Field use:

Comfort: As a large, side sleeping, woman, I've always needed the extra thickness and padding of a full length Thermarest LE. With the REM air core pad, I can easily get the necessary comfort to get a full night's sleep while saving myself nearly a pound of weight.

Design observations: The pad is designed in a mummy shape to fully integrate with the mummy shaped top bags offered by Big Agnes. They are also sized to match the bags and are therefore the same length as the bags. Three quarter length pads are not an option.

For lightweight packing, I found the pad adequate for providing a barrier along the back of my lightweight backpack. Even though it does not provide as much support or padding as a stiff closed cell foam pad or even a self-inflating open cell foam pad (full-length Thermarest LE), it is adequate for smoothing out any pressure points other gear items might have formed as they got packed in my backpack.

With the tubular air channels, this pad resembles the type of water raft you might see used in backyard pools or at the beach.

Temperature observations: The REM Air Core pad is only rated to 32 degrees. Brad, at Big Agnes, made sure I was aware of this givent that I was planning on using the pad with a 20 degree bag. I declined knowing that would have eliminated the weight savings I was seeking. My intention, knowing many closed cell pads weigh less than a pound, is to try using a thin closed cell pad in conjunction with the REM Air Core pad to extend the temperature range of the pad to match the bag rating and still weigh less than my Thermarest.

Camping under the stars at the RPH shelter in New York on a cold night on my way home from Trail Days, I did wake up cold early in the morning and could tell I was cold from the lack of insulation beneath me. I pulled my old rectangular closed cell foam pad out and put it inside the Zirkel so that I was sleeping on top of that and the REM Air Core pad. It made the bag a little more tight fitting, but immediately solved the insulation problem.

I anticipate doing a bit of testing to find a thinner closed cell foam pad that I can cut to shape and put in the sleeve with the REM Air Core pad to extend the Zirkel system to 20 degrees or so.

Pluses:

The light weight of the pad for the support it provides.
The pad is plenty cushy, even for heavier bony side sleepers.

Minuses:

The pad is a warm weather pad.

Summary: The REM Air Core pad has become my pad of choice for hiking in temperatures above freezing. Coming from an already fairly luxurious full-length Thermarest LE, I find I sleep equally well on the REM Air Core pad. The weight savings (15 oz.) over the Thermarest makes the pad an attractive option for those hiking in warm weather.

[I am providing the following information as a service to those that would otherwise be curious. According to their web site, Big Agnes does not recommend the REM Air Core pads for use in temperatures below freezing.] I believe with a thin closed cell foam pad, cut to size, the REM Air Core pad may prove to be a lighter option than my full-length Thermarest LE for cool spring and fall hiking with limited nights in the 20 to 32 degree range.

I do NOT recommend the REM Air Core Pad for winter hiking in very low temperatures. I have serious concerns about ice buildup in the pad due to the introduction of warm moist air into the pad each time it is inflated. I do expect moisture to accumulate in the pad over time and use of a pad with such a buildup in such cold temperatures could result in damaging ice forming inside the pad. Additionally, ice buildup could prevent the pad from inflating properly should moisture build up and then freeze after deflation. Recommendation for Big Agnes' consideration:

Use Pertex or sylnylon stuff sacks. Both would be lightweight, water resistant options.

Questions for other REM Air Core pad users:

Are there any "tricks" to deflate the pad? I find I have to press air out from the bottom of the pad, and fold sections up until I reach the head area. The I unfold and fold lengthwise once, and then widthwise twice to make a "pad" the appropriate size for back protection in my backpack.
Also, according to the Big Agnes web site, when using the REM Air Core pad with a Big Agnes sleeping bag, you can leave the pad in the bag sleeve and put both into the sleeping bag stuff sack. While the sleeping bag stuff sack seems to have plenty of room for both the bag and the fully deflated pad, I have not been able to get enough air out of the pad while it is still in the sleeve to make this work. Are there any tricks for this "problem?"

While I probably will not be stuffing the pad with the bag, I am curious how that works and would like to successfully try it at least once.

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Reviews > Sleep Gear > Pads and Air Mattresses > Big Agnes Air Core Mummy Pad > Mara Factor > Field test

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