A sleeping bag is one of the most important pieces of equipment for a long-distance hiker. Not only does it have to be comfortable enough to give you that much needed sleep between those 25-30 mile days, but it also has to be light enough not to break your back when hiking those very same 25-30 mile days. Comfort in camp versus comfort on trail.
For a long time I was using a Mountain Hardwear Phantom 32 (0 Celsius) down sleeping bag: On the John Muir Trail in 2011, on the Pacific Crest Trail in 2012 (where I had it replaced), on the Continental Divide Trail in 2015, and then on the Te Araroa Trail in 2015/2016. The truth of the matter though, is that I was never completely sold on down bags. Sure, down bags are lightweight and they compact real well. But down bags are also really, really expensive. Usually twice the price of a similarly rated synthetic bag. And my main grievance with down bags is that the the down tends to clump up and shift around in the baffles, thus causing cold spots. Neither of the two Phantom 32 bags I have owned ever felt like a proper 32-degree bag.
When learned that Mountain Hardwear had come out with a new lightweight synthetic sleeping bag, the HyperLamina Spark 35, I was intrigued: At 788 grams (27,8 oz) for the long version it’s a mere 72 grams (2,5 oz) heavier than my 2012 Phantom 32 at 716 grams (25,3 oz). And in spite of the name the HyperLamina Spark 35 actually has the same temperature rating as the Phantom 32, 32 degrees Fahrenheit / 0 Celsius. At $235 it was half the price of getting a new down bag. I decided to give it a shot!
Mountain Hardwear HyperLamina Spark 35 key features:
- EN Rating: T-LIMIT: 32 F / 0 C
- Synthetic Thermal.Q insulation that is welded on to outer fabric – no penetrating seams
- Snug mummy cut
- Half-length front zip (to reduce heat loss)
- At 185 cm (6 ft 1 in) I opted for the long version
- 788 grams (27,8 oz) w/o compression stuff sack
- Price paid: $254 ($235 + tax) – find on Amazon.com
I put the HyperLamina Spark 35 through the wringer on 400 miles of the Hayduke Trail in February and March of 2016. It performed brilliantly. If I had taken my Phantom 32 down bag I know I would have been cold and miserable. Instead I was rather nice and comfy. No cold spots! The HyperLamina kept me nice and warm during all but the coldest nights (which the bag was never rated or intended for anyhow).
Sure, the HyperLamina is a little bit bulkier than the Phantom 32, I use a 10L dry sack for the HyperLamina vs. an 8L for the Phantom, and a little bit heavier, 788 grams (27,8 oz) for the HyperLamina versus 716 grams (25,3 oz) for the Phantom. But I’m OK with that. Considering the fact that the HyperLamina eliminates the problem with cold spots, and that it’s $200 cheaper than comparable down bags, makes this a no-brainer for me: I’d buy the HyperLamina Spark 35 instead of a down bag.
I’m looking to test out this sleeping bag. What was the coldest temperature at which you used it? If you were cold, do you think wearing base layers would have eliminated the problem? Thanks!
Hi Bianca,
The coldest night I’ve used the HyperLamina Spark in was probably around -7 to -8 Celsius. I always wear a base layer, both to add warmth and to keep the bag clean, but even with a base layer I was cold at this temperature. I definitely felt that I had pushed the bag beyond it’s limits. So if you plan on using the bag for below-freezing temperatures I would suggest that you look into other bags instead. E.g. MH makes a version that is rated down to -6 Celsius, the HyperLamina Flame, but I have not used that one myself.
Cheers
Stein