Therm-a-Rest Questar Sleeping Bag Review

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Getting a restful night’s sleep on a cold winter camping night primarily comes down to three things: shelter from the elements, a barrier between you and the ground, and a way to insulate yourself from the cold air. Accomplishing these is usually done with a four season tent, a good sleeping bag and a ground pad. Let’s explore the good sleeping bag category.

For this camping season Therm-A-Rest has released the Questar 0, which is packed with performance-enhancing features needed for cold-weather camping, from SynergyLink^™Connectors to ThermaCapture^™ Seams, and crafted with water-resistant 650 fill Nikwax Hydrophobic Down^™ all to help keep the cold at bay.

If you’ve ever shopped for sleeping bags, you probably noticed that a temperature rating (a.k.a. comfort rating) usually appears in the product name, Therm-a-Rest Questar 0F/-18C. Sleeping bag temperature ratings are tested by the manufacturer, either according to their own set of standards or in accordance with EN 13537 standards.

When a company uses its own standards to measure a sleeping bag’s temperature rating, that rating is often the coldest temperature a sleeping bag is designed to be used in (and hopefully still keep a person warm). However, not all companies use the same standards or testing methods. Also, different people have different comfort zones. What one person considers “warm” may be too cold for another person.

Thus, unless you dress in warm clothing at night, consider adding 10 degrees to the factory temperature rating of any sleeping bag. For instance, if Sleeping Bag XYZ is rated for 0°F, then it should be used in temperatures of 10°F or warmer. If the temperature gets down below 0°F, you probably won’t get hypothermia, but you might not be warm and cozy either, unless you add additional layers of clothing. This is just a general rule, as everyone’s comfort level can vary.

The EN 13537 is a three-part temperature rating system that has been used in Europe for several years. This system has been adopted in the United States by some brands. Sleeping bags that feature an EN 13537 rating are assigned three distinct temperature ratings according to a standardized laboratory test. Keep in mind that this rating system assumes that the camper will be sleeping on a one-inch thick sleeping pad, will wear top and bottom base layers, and will also wear a cap or beanie. The advantage of the EN 13537 system is that it offers multiple temperature ratings, which make it easier for the consumer to choose an appropriate bag. This system provides three separate ratings:

Comfort rating is mainly geared toward people who tend to sleep a little colder. This rating assumes that the user will sleep in a relaxed, supine position. If you tend to chill easily at night, choose a sleeping bag based on this EN 13537 rating.

Lower limit rating is geared toward people who tend to sleep a little warmer. This rating assumes that the user will sleep in a curled position. If you consider yourself to be a warm sleeper, choose a sleeping bag based on this EN 13537 rating.

Extreme limit rating is a survival rating only that designates the temperature at which a sleeping bag may or may not help prevent hypothermia. In other words, the sleeping bag may keep a person alive overnight at this temperature, but the person will most likely not be warm or comfortable.

Features of the Therm-a-Rest Questar

• 650 fill Nikwax Hydrophobic Down^™: Stays drier and maintains loft 60 times longer than untreated down.
• ThermaCapture^™ Seams: Traps radiant body heat and retains warmth without adding bulk or weight.
• SynergyLink^™ Connectors: Integrate the bag with a mattress for optimal comfort and efficiency; removable for versatility.
• Zoned Insulation: Maximizes warmth and saves weight by intentionally placing fill where you need it most.
• Quilt and Blanket Loops: Customize your sleep system by layering quilts or tech blankets for increased warmth.
• Toe-asis^™ Foot Warmer Pocket: Ergonomic toe box that rapidly warms cold feet in a pocket of warm down.
• Responsible Down Standard Certified: Certification that ensures that the waterfowl in the down supply chain are treated humanely.

With all down bags that are in a compression sack, you will always want to pull the bag out at least 30 minutes or an hour before it’s time to go to sleep. This will gives the bag time to fully restore its loft before you bed down for the night.

On the note of loft, the Questar is crafted with water-resistant 650 fill Nikwax Hydrophobic Down which absorbs 40% less moisture than untreated down. This will keep you warmer over a greater range of conditions, and allows the bag to dry and restore performance faster for those times when it is a get up and go morning.

In addition to the Nikwax loft, the Questar incorporates ThermaCapture Seams and Zoned Insulation that traps radiant body heat and maximizes warmth allowing this bag to keep you toasty warm in sub-freezing temperatures.

The Toe-asis foot warmer pocket installed in the Questar is an ergonomic toe box that quickly warms up your feet and keeps them warm all night by offering a baffled pocket of insulation in the footbox, just slide your feet in for maximum warmth. Leave them out and you’ll still benefit from an extra layer of insulation in the foot of the sleeping bag.

The SynergyLink™ Connectors on the Questar integrate a mattress and the bag. They make sure you stay on your mattress while giving the ability to roll freely for the best nights rest possible. Two elastic bands create a snug fit around any mattress up to 25 inches (63.5 cm) wide, keeping the bag centered and eliminating problems with sliding off your mattress or getting your bag twisted around you.

While the temperature I tested the Questar in didn’t quite make it down to the zero mark, it was in the teens for most of the night and being only dressed in a base layer, the Questar kept me plenty warm. Individual comfort zones being what they are, I have no doubt that this bag would have easily kept me warm at temperatures hover around or even slightly below the zero mark.