NEMO Forte 35 Synthetic Sleeping Bag Review

The NEMO Forte 35 is an affordable, lightweight, Primaloft synthetic-fill sleeping bag with a “spoon” shape for people who don’t like the draftiness of a quilt nor the confined feeling of a mummy bag. The NEMO Forte has lots of unique features and interesting design elements. Ultimately, we believe the Forte 35 is best used as a mild temperature sleeping bag for backpackers and campers who sleep on their side or back but don’t change position much in the night.

Specs at a Glance

• Minimum Weight (from manufacturer): 2 lb, 2 oz / 960 g
• Tested weight: 34.7 ounces (2 lb, 2.7 ounces) / 984 g for the bag; 2.9 ounces / 82 g for the compression sack
• Packed Size: 11.5 x 9.0 in dia / 29 x 23 cm dia
• Temp Rating: 35F / 2C
• ISO Lower Limit 31F / -1C
• Shell fabric: 30 D Polyester Ripstop w/ DWR
• Liner fabric: 20D Nylon Taffeta w/ DWR
• Fill Type: Primaloft Synthetic
• Fill Weight 1 lb , 1 oz / 470 g
• Fits Up To 6′ / 183 cm
• Shoulder Girth 64 in / 163 cm
• Hip Girth 59 in / 150 cm
• Knee Girth 62 in / 157 cm
• Included: Compression stuff sack, mesh storage bag

We tested the 35 Degree, Regular length, Men’s model; NEMO also makes the Forte in Long length and a 20F version, both of which are also available in Women’s models (with more insulation at same temp rating, making them warmer bags). The Men’s and Women’s models have zippers on opposite sides so you can zip them together into a double bag.

The NEMO Forte 35 uses Primaloft synthetic insulation. While synthetic insulation is less durable than down (it will pack down and lose insulative power when compressed repeatedly), it is also less expensive and more resistant to losing loft in wet or very humid conditions.

Spoon Shape

This is a signature feature of NEMO sleeping bags: a cut that has extra width in the shoulders, hips, and knees, which allows you to bend your knees if you’re sleeping on your side, just as you do in bed at home. The contouring of the spoon shape is a middle ground between a classic rectangular bag and a snug mummy and allows for a lot more flexibility of sleeping positions than a mummy bag. A tradeoff of the extra room is that there’s more dead air space inside the bag for your body heat to have to warm up.

Oversized Hood with Integrated pillow pocket The Forte has a pocket built-in to the inside of the hood, that you can stuff a puffy jacket (or one of NEMO’s “Fillos”) into to make an integrated pillow that won’t slip and slide as you sleep. If you’ve ever played hide-and-seek with your pillow overnight, you can see the benefit. The hood is therefore intentionally oversized to accommodate a pillow inside it–without a pillow, the hood will be oversized even cinched all the way down (and I have a big head) but it does still create a good seal around your face when lying on your back, due to a draft tube around the hood’s perimeter. Since the hood is oriented facing upwards, if you sleep on your side, the side of your face is exposed, but I was still able to keep my ears covered.

Blanket Fold Draft Collar

In the same way that the spoon shape of the Forte is a reaction to a confining mummy bag, the Blanket Fold is NEMO’s alternative to a tight neck draft tube and a different way to seal the gap around your neck and chin and prevent warm air from escaping the bag.

Instead of cinching it with a drawstring or closing it with Velcro, you just tuck it around your chin like tucking in a blanket or leave it hanging out if you don’t need it on warmer nights. It’s soft and cozy, and easy to adjust but can flop into your face if you leave it untucked as there is nothing to hold it in place.

Small Essentials Pocket

There is a small accessory pocket on the left chest that opens with an invisible zipper (like the kind often used on dresses) with a tiny metal zipper pull. These kinds of pockets are useful to keep the batteries of your electronics warm overnight. I have an iPhone 6s in a case, and found it just barely fit in the pocket–if your phone is any bigger it won’t. After the first couple of nights with the bag, I noticed I had stretched out some of the threads in the pocket seam by putting my phone in it.

Thermo Gills

Thermo Gills are zippered pockets on the chest of the bag that reveal a less-insulated section of bag underneath, so they can dump heat and allow the bag to be used in warmer temps. They use the same kind of invisible zipper and tiny zipper pulls as the pocket described above. The Thermo Gills’ zippers are only accessible from the outside of the bag, so you have to unzip the main bag zipper and stick an arm out to open or close them. As the NEMO Forte 35 is already a mild-weather bag (more on this below), I imagine this feature having greater utility on the colder-weather model because at the temperatures I’d want to open the Forte 35’s Thermo Gills, I would be unzipping the main zipper anyway.

Snagging Zipper

The zipper manufacturer YKK created a no-snag plastic cover that snaps onto zipper sliders to push extra fabric out of the zipper path to prevent it from getting stuck in the zipper. I’ve started to see this small plastic cover showing up on more and more sleeping bag zippers over the last couple of years. But it’s not a panacea because it’s not paired with a stiffener along the draft tube, something the bag should have anyway. The Forte has two zipper sliders, so you can vent the feet with the rest of the bag zipped up. There’s an insulated draft tube running along the length of the zipper, with a fabric strip that is not as silky as the sleeping bag liner, but it’s not a stiffener and can (and does) still get caught in the zipper.

I found the Nemo Forte zipper to snag almost every time I used the zipper, whether for ventilation or to get up in the night. This was extremely frustrating because each time I had to sit up, turn on my headlamp, and try to delicately remove the fabric from the zipper teeth: it was never a quick process.

Temperature Rating

The NEMO Forte 35F is rated according to ISO/EN Standards which include a range of temperatures at which a sleeping bag is usable, from Comfort to Lower Limit. Now that we have this universal standard, I think it’s most helpful when companies publish both the comfort and limit temperatures as a range.

Of course, this makes naming conventions more difficult, as most sleeping bags have a specific temperature as part of their name. This means it’s up to the manufacturer to decide how they want to distill the tested ranges into the naming of their bag. The Forte’s specifications sheet shows that its lower limit is 31F, so I think naming it as a 35F bag is overly optimistic for many users. The Comfort rating for the Forte is not listed. ISO/ EN Standards describe the Lower Limit Transition Range as the temperatures at which a standard man is “in a situation of fighting against cold (posture is curled up inside the sleeping bag), but in thermal equilibrium” and not shivering.

I found that from the low 30s into the low 40s I was consistently cold using this bag, even when stacking multiple sleeping pads below me, wearing long underwear, and adding a down jacket as the temps dropped. I am short (5’4”) and pretty lean, and know that I sleep cold, but I’ve found temperature ratings from a number of other manufacturers to be more accurately (conservatively) rated than the Forte. For my own use, I would relegate the NEMO Forte to temps above 45F. Recognize too, that on average, women sleep colder than men and need more insulation. The Women’s Forte 35F bag is based on a Comfort rating of 32F. A man who knows he tends to sleep cold may want to go for the Women’s version of this bag.

Assessment

The NEMO Forte 35 is a spoon-shaped synthetic sleeping bag designed for side sleepers. As a rotisserie sleeper myself, I had a hard time using this bag. As I moved from side to side, I got tangled up. When I’m in a traditional body-hugging mummy bag, I tend to stay more in one place, and when I do move, the bag moves with me. There is enough girth in the Forte that the bag didn’t turn when I did, so I found the zipper ending up in a bunch of different places, having to readjust the Blanket Fold, and fighting the oversized hood.

I think the ideal user for this bag is a side sleeper who tends to stay in one position through the night or a back sleeper who likes a roomier cut than a traditional mummy bag. The ideal user would also be someone who runs warm or is planning on using the Forte in mild temperatures.

Disclosure: NEMO provided the author with a sleeping bag for an honest review.

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