Moutain Hardwear's UltraLamina 15 Sleeping Bag Editorial Review

When deciding on a cold weather sleeping bag, the decision often comes down between down or synthetic. Down usually wins out because the flat truth was that down is warmer than synthetic, and the fact that it stuffs smaller and weighs less also didn’t hurt any. Down has its downsides as well- two of them are pretty big- if you get it wet you’re screwed, and the price will make you cringe. So, as a result, down usually rules the nest in the really cold temps/backcountry and synthetic makes a good car camping/mild weather option.

For years, manufacturers have been improving synthetic insulation in sleeping bags, and this year, Mountain Hardwear took a huge leap forward and just made the line between down and synthetic a little fuzzier. At the 2006 Summer Market, they introduced me to the UltraLamina 15 degree bag.

Mountain Hardwear's UltraLamina Bag Mountain Hardwear Mountain Hardwear's UltraLamina Bag. Photo: Mountain Hardwear.

After the show, I talked with my rep at the company and they sent me a sample in November to try out. The bag has definitely been tested- since I wasn’t able to get away that much during the winter, I sent it out with my friends when they went on their trips and their feedback is included in this review.

First, the specs:

The bag is a 15 degree synthetic bag filled with Mountain Hardwear’s new proprietary insulation called ThermicMicro. It’s got a 20D Micro Ripstop Nylon shell, weighs about 2.86lbs, has 5.5” of loft, and comes with a compression sack to stuff it down to as small as 8” x 11”. The bag retails at $190 for the regular length and $200 for long.

The bag also has some special features. It’s a mummy bag, cut a little more snug than a standard bag. It also features welded construction where the insulation is, rather than using stitching. There is also a face gasket at the hood, which is nice when its really cold out. Finally, there is an internal pocket at the shoulder- nice for a headlamp or your keys.

So, let’s do some comparisons Now, I’ve never owned a down sleeping bag, but I’ve certainly debated having one. The main reason I don’t own one is because I don’t do snow or backcountry- I’m mostly a car camper. If I make some annoyingly glaring error here, please forgive my ignorance and correct me in the comment section!

For consistency, we’ll compare specs on 3 Mountain Hardwear bags- the UltraLamina 15, the synthetic 2nd Dimension 15 (my bag), and the down filled Phantom 15. Performance comparisons will be made between the UltraLamina and the 2nd Dimension.

First the weight- The Phantom still wins out at 1lb, 15oz, the UltraLamina comes in second at 2lbs 13oz, and the 2nd Dimension is the heaviest at 3lbs 5oz. All weights are for regular length. You’ll note, though, that the UltraLamina is a half a pound lighter than its predecessor (which is the average weight for a synthetic bag)- Mountain Hardwear went to great lengths to shave the weight on this one- 1/3 length zips, no stitching (less thread), and a lighter shell- but most of the weight savings still comes from the new insulation.

Second, stuff size. The Phantom’s specs tell us that it stuffs down to 8” x 14”, so we’ll have to believe them. Let’s say it stuffs to 8” x 12” to be generous. The 2nd Dimension stuffs to 8” x 19.5”. The UltraLamina wins this one- it stuffs down to a tiny 8” x 11”! A note on the stuff sizes- Mountain Hardwear’s website lists the stuff size for the UltraLamina at 8” x 17”- I assume this is a non-compressed size in its stuff sack. My sample’s stuff sack broke at the compression strap the first time I stuffed it, so I purchased a Sea to Summit compression sack for it, and its measurements are the ones I am using.

The UltraLamina next to the 2nd Dimension. John Wilder The UltraLamina next to the 2nd Dimension. Photo by: John Wilder.

Finally, let’s talk about warmth. The bags are all rated to 15 degrees, so in theory, they should provide about the same level of comfort in 15 degree weather, especially since they are all made by Mountain Hardwear. I wish I could have tested a down for comparison, but alas, only the two synthetics were tested. The 2nd Dimension has been in use for about three seasons- roughly three weeks worth of use a year. The UltraLamina has been used for about 10 nights in three different locations at different temperatures. I will also note that I sleep cold- if the temps are below about 65, I’m shivering.

I can say without doubt that the UltraLamina is a significantly warmer bag than the 2nd Dimension. The 2nd Dimension was comfortable for Yosemite in the summer if I left the tent door open and was just relaxing. In the winter at Joshua Tree, even with the hood up and pulled tight, I could still feel the cold. The UltraLamina, on the other hand, was nicely toasty at Joshua Tree in those same temperatures- the lows were around 18 on one trip, and the bag felt great.

Now, to the bag itself as a product. Overall, it’s a good bag because it does the one thing I want it to really well- it keeps me warm on a cold night. There are, though, some not so great things about it that I’ll note here.

First, the zipper situation- it doesn’t really bother me, but it might bother some. Instead of having a full length zipper on one side, the bag uses a 1/3 length zipper on both sides. This means you have to slide in and out of the bag. Not a big deal, but it may annoy some people.

The UltraLamina fully open- the 1/3 zippers may not appeal to some people John Wilder The UltraLamina fully open - the 1/3 zippers may not appeal to some people. Photo by: John Wilder.

Second, the compression sack- it’s weak. The straps were a quarter inch wide and one broke the first time I used it. Now, I will note that the sample I had was not new when I received it, so I do not know what sort of abuse it went through before I got my hands on it, but I still suspect that you’ll be buying a new sack for it at some point. Hopefully Mountain Hardwear will fix this one design flaw in years to come.

Third, temperature regulation. My 2nd dimension had a nice baffle system to help regulate my temperature in non-freezing temps. This feature was really nice during summers at Yosemite. I spent four nights in Zion recently were night time temps were in the mid 40s, and in the early evening, I was so hot in the bag I could hardly stand it. On the last night, the warmest one, I soaked the bag with sweat! Mountain Hardwear notes that you can use the zips for temperature regulation- and you probably can, but again, I sleep cold, so the air outside was cold enough that I wanted some cover, but the bag itself was way too warm to be in. Of course, I’ll also note that I’m not complaining about this- having a synthetic bag that was too warm made me pretty happy, but it does mean that my 2nd Dimension will continue to see summertime use in Yosemite.

Overall, Mountain Hardwear has made a really nice bag. It’s very warm for the temperature rating- I’d be willing to be that someone who sleeps warm could sleep down to zero or so in this bag. I like that its noticeably lighter than my old bag, but more importantly, I love how small it compresses- I always hated lugging around that giant stuff sack, and now I’m in heaven with my tiny ball of synthetic happiness! I still think that down will probably win out for a backcountry bag- mostly due to the weight, but I do believe that Mountain Hardwear has made a big step forward with this bag.

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Full Disclosure: The manufacturer of this product provided it free of charge to rockclimbing.com for review. Rockclimbing.com then provided this product as compensation to the reviewer. This company does not currently advertise on rockclimbing.com. April 15, 2007