Guest - Not logged in 

Reviews > Sleep Gear > Sleeping Bags > Therm-a-Rest Quester 0 bag > Test Report by Alyssa Kimber

Therm-a-Rest Questar 0F/-18C Sleeping Bag

Test Series by Alyssa Kimber

Tester Information
Name:  Alyssa Kimber
Age: 24
Gender: Female
Height: 5' 10" (1.8 Meters)
Weight: 130 Pounds (59 Kilograms)
Email address: alyssakimber at hotmail dot com
City, Province, Country: Fernie, British Columbia, Canada

Backpacking Background: I started backpacking last year after moving from the prairies to the Kootenay region of British Columbia. I’m relatively new to backpacking but I have significant outdoors experience having enjoyed camping and day hiking for many years. My trip length is generally one to three nights and ranges from prairie hikes to mountainous terrain. I am a 3-season hiker at present but I plan on extending my trips into the winter season as I pick up more gear. My pack weight varies depending on the trip, but I tend to sacrifice weight savings for comfort.

Initial Report

March 1, 2018

Product Information & Specifications
Manufacturer: Therm-a-Rest
Year of manufacture: 2018
Manufacturer web site:
Sizes: Small, Regular, Long
Tested Size: Regular
Manufacturer's listed measurements:
    Fits: 72 in (183 cm)
    Weight: 3 lbs (1.36 kg)
    Width: 31.5 in (80 cm)
    Length: 79 in (201 cm)
    Girth, shoulder: 63 in (160 cm)
    Girth, hip: 61 in (156 cm)
    Girth, foot box: 46 in (117 cm)
    Foot width: 23 in (58 cm)
Actual Measurements:
    Weight of sleeping bag: 2.83 lb (1.28 kg)
    Weight of storage sack: 3.07 oz (87 g)
    Weight of SynergyLink Connectors: 1.66 oz (47 g)
    Weight of stuff sack: 1.23 oz (35 g)
    Width: 31.5 in (80 cm)
    Length: 79 in (201 cm)
    Width, shoulder: 31 in (79 cm)
    Width, hip: 31.5 in (80 cm)
    Foot width: 19 in (48 cm)
EN (European Norm) Comfort: 14F/-10C
EN Limit: 0F/-18C
EN Extreme: -40F/-40C
Shell Fabric: 20D Polyester Ripstop w/Durable Water Repellent (DWR)
Liner Fabric: 20D Polyester Taffeta, Printed
Zipper side: Left       
MSRP from web site: $329.95 USD

The Therm-a-Rest Questar 0F/-18C sleeping bag arrived on February 28, 2018. Included with the sleeping bag was a stuff sack, storage sack, and the "SynergyLink Connectors". The bag is light blue in color with lime green accents and a grey, printed interior. The bag is mummy-style and hooded. The zipper is located on the left-side of the bag, extending from approximately calf-height to the hood of the bag, with a snap at the top of the zipper. The "ThermaCapture" seams provide about 1 inch of seam on either side of the zipper and are stated to "trap radiant body heat and retain warmth without adding bulk or weight". The sleeping bag includes a face-flap and draw-string hood as well as a zippered pocket on the right side for holding small items such as a cellphone or watch. The sleeping bag has zoned insulation, with noticeably more fill at the feet, head, and top of the bag. The "Toe-asis" Foot Warmer Pocket is an additional layer of down sewn into the footbox as an optional "pocket" for the feet. Feet could also be placed on top (outside) of the warmer pocket. Small plastic loops are sewn onto the bottom of the bag for integration with the SynergyLink Connectors. The fill material is 650 fill Nikwax Hydrophobic Down, stated to "stay drier and maintain loft 60 times longer than untreated down." The SynergyLink Connectors appear to be made of polyester and elastic and are designed to reach around a mattress and secure it to a sleeping bag to ensure the bag stays centered and does not slip off. The stuff sack is made of a grey polyester material with lime green drawstring and the storage sack is made of blue polyester and grey mesh with a lime green drawstring.

Therm-a-Rest now has the Questar 0F/-18C posted on their website. The item appears to be exactly as advertised on the website. I did note that it specifically states "storage sack and stuff sack included", which leaves out the SynergyLink Connectors. However, the SynergyLink Connectors are included in the product description and in the images, which would confuse me as a consumer as to whether they are included or not.

All items

Initial Impressions
My first impression is that the bag looks very cozy and comfortable - which I believe comes from how lofty the bag is.  I tried the zipper and closure snap out a few times and found no snags or issues with those. The ThermaCapture seams seemed to help keep the polyester material out of the zipper's path. I had a look over the bag for any tears or loose threads and found none. It appears to be well-constructed.

Since the sleeping bag was not posted on the website prior to my receiving it, I did not know what colour the bag would be. I was happy with the bold colors of blue and lime green. When I climbed inside the bag for a first test-run, the first thing I noticed was the zoned insulation. There seemed to be a lot of extra insulation around the lower legs and feet as opposed to the torso. The next thing I noticed was the length; it fit me well at 70 in (178 cm). As I tossed and turned a little to test out the width, I did note the significant difference in shape between this bag and my current sleeping bag which has a "peanut" shape. There is less width in this bag at the knees which prevents me from laying as I usually do on my side. It is still possible to lay on my side but I can't stretch out as much as I am used to. I tried out the hood which fit comfortably around my head and also stuck my feet into the foot warmer pocket. You do have to "feel" for the pocket to make sure your feet are sitting in it and not on top of it. I then turned the bag inside out to get a better look at the foot warmer pocket and the inside of the bag. I liked the printed material inside (more "fun" than plain grey). The foot warmer pocket looked well-constructed, and simple; just an extra layer of down for your feet! I included a photo of the foot pocket below. Overall I was impressed with the features of the bag (foot warmer pocket, hood with drawstrings, SynergyLink Connectors, and zippered pocket for personal items), it's appealing colors, and obvious comfort.

Foot pocket

I was not impressed with the stuff sack as it appeared quite large and the material (grey polyester) unappealing. I tested the sleeping bag inside the stuff sack and I'm quite sure I could fit it into a smaller compression sack. This is disappointing as it means I won't get much, if any, use from the included stuff sack. The stuff sack is pictured below beside my 32 L avalanche bag. I was impressed with the storage sack. I like that it is large and mesh, allowing the sleeping bag to breathe. It also has two drawstrings which allows me to choose the volume and make the storage sack smaller if I want to. I was happy to find the SynergyLink Connectors are very light-weight which will make the decision to bring along an "unnecessary item" very easy.

Stuff Sack

My only concern with the bag is how it will perform at it's rated temperature. I did not know that a sleeping bag "rated" to 0F/-18C is actually in the "transition" range and is rated as comfortable at 14F/-10C. I am eager to see how it performs at the transition temperature (I hope well!).  I'm looking forward to testing out the bag on my upcoming trip to a backcountry hut.

Field Report

May 21, 2018

Field Report Test Locations
During the field test period I have taken the sleeping bag on one backcountry ski trip to a backcountry hut, two winter backpacking trips, and a supported bike-packing trip. The backpacking trips were situated close to Fernie, British Columbia and the bike-packing trip began and finished in Banff National Park, Alberta. The backpacking trips were located in backcountry, mountainous terrain with vegetation typical of subalpine forest. I stayed within the treeline on both trips. Elevation ranged from 3100 ft (950 m) to 6000 ft (1850 m). The bike-packing trip was a highway trip through the mountains with elevation between 2600 ft (800 m) and 5800 ft (1800 m).
Trip #1 Test Conditions and Performance
Location of Trip #1: Tunnel Creek Hut, Lizard Range, British Columbia, Canada
Length of Trip: 2 days, 1 night (March 2-3) 
Pack Weight: Not weighed - approximately 10 lb pack + 10 lb snowboard on my back for the hike up, traded for 2 lb snowshoes on my back for the trip down
Distance (roundtrip): 10 km (6 miles)
Elevation Gain: 900 m (3000 ft)
Precipitation: Approximately 20 cm of fresh, dry snow (8 inches)
Temperature Range Outside: -5 to -10 C (23 to 14 F)
Temperature Range in Hut: 0 to 15 C (32 to 59 F)

I carried a 32 L avalanche bag for this trip and tied the sleeping bag to the bottom of the pack using the straps on the compression sack (see photo below of the setup). I used a compression sack to store the sleeping bag on this trip, as opposed to the stuff sack that came with the sleeping bag, because I needed the straps of the compression sack to attach the sleeping bag to my avalanche bag. The compression sack also packs the sleeping bag much tighter than the included stuff sack, which I find to be more practical. The sleeping bag felt packable and light throughout the trip; carrying it did not bother me at all. I chose to leave the SynergyLink Connectors at home as there were large foam mattresses provided at the hut which would not slide around in the night.


I am happy to report the Durable Water Repellant (DWR) on the shell fabric and hydrophobic down performed amazingly well. I lost my balance at one point (because of the awkward weight of my snowboard) and I managed to tip over into a small creek with about 4 inches of running water. I landed on my left side and was unfortunately stuck for about 30 seconds as I struggled to right myself (again, thanks to the awkward weight of my snowboard). This gave me, and my sleeping bag, plenty of time to get wet! I unpacked the sleeping bag about 4 hours later after we arrived at the hut and am happy to report I found no dampness at all. The bag was in the compression sack when it was exposed to water so that also assisted with keeping it dry. When I unpacked the sleeping bag at the hut I noticed a few down feathers had escaped but I could not see specifically where they came from.

I was very comfortable and warm in the sleeping bag throughout the night. The temperature in the hut when I first went to sleep was around 15 C ( 59 F) so I slept with the sleeping bag unzipped to allow for some temperature control - there are no vents on this sleeping bag. I woke up later in the night and the temperature had dropped to around 0 C (32 F). At this point I was chilly so I zipped up the bag completely and was quickly warm and comfortable again. I did not like the restricting nature of the mummy-shaped bag as it prevented me from stretching my knees out while sleeping on my side. I liked the hood of this bag as it extended over my eyes and kept any infiltrating light out.

When I returned home and unpacked the sleeping bag I noticed a loose thread on the inside of the hood, about 3 inches in length. This is not affecting the performance of the sleeping bag at present but I will pay attention to it on future trips in case it worsens.

Trip #2 Test Conditions and Performance

Location of Trip #2: Hartley Lake Recreation Area, Mount Hosmer, British Columbia, Canada
Length of Trip: 2 days, 1 night (March 15-16) 
Pack Weight: 22 lbs (10 kg)
Distance (roundtrip): 10 km (6 miles)
Elevation Gain: 350 m (1150 ft)
Precipitation: Light rain/sleet on trip in, scuff of snow on tent overnight
Temperature Range: -8 to 4 C (18 to 39 F)

I used my backpacking specific bag for this trip and used the buckle straps on the bottom of the backpack to carry the sleeping bag. Again, I used the compression sack as opposed to the included stuff sack due to packability. Again I was able to test the water resistant properties of the bag as it was exposed to light rain and sleet for about 2.5 km (1.5 miles) until I realized I brought a rain cover with me. At this point I put the rain cover on my bag but it was already very wet, including the compression sack with the sleeping bag inside it. However, when I unpacked the sleeping bag at my campsite 1 hour later, I once again found no dampness. See photos below of the unpacked sleeping bag.
HartleyLake HartleyLake2

I did not have a great sleep this night as I was setting up my site in a hurry and did not have time to level out my spot. Therefore I was sleeping on a bit of a slope and kept sliding off my mat. To compound the issue, I had forgotten to bring the SynergyLink Connectors, whose purpose is to keep the sleeping bag attached to the mat! I now have a baseline for how the sleeping bag works without the SynergyLink Connectors and I look forward to comparing the two scenarios on future trips.

The overnight temperature on this trip was around -8 C (18 F) which is still within the sleeping bags rated comfort range. I was also wearing a wool ninja-suit, a fleece sweater, wool socks and hut booties inside my bag. My feet were also in the foot warmer pocket. I was sufficiently warm but the temperature was not completely comfortable. Next time I would wear additional layers inside the bag. I had the bag zipped up completely the entire night and the hood pulled tightly around my head. I was happy with the drawstring feature as it kept the hood tightly in place throughout the night. With the sleeping bag body and hood pulled together it was a little stuffy so I had to leave a slit open for breathability.

I really noticed the zoned insulation on this trip and I have to say I am not a fan. Each time I would lie on my side, the sleeping bag would shift and the "bottom" of the bag would become exposed. I could tell immediately the bottom of the bag had less insulation than the top. It felt quite strange lying on my right side with the top half of my back (my left side) warm while the bottom half of the back (my right side) felt cold and drafty through the thinner insulation. I only noticed this effect around my lower back. The upper torso and legs appeared to have sufficient insulation. For this reason, I felt sufficiently warm only when I laid "mummy-style" - in a position where the thinner insulation was pressed against my sleeping mat. The bag was built for a mummy-style sleeping position so it does serve it's purpose as intended.

Trip #3 Test Conditions and Performance
Location of Trip #3: Burton Lake, British Columbia, Canada
Length of Trip: 2 days, 1 night (March 29-30) 
Pack Weight: 22 lbs (10 kg)
Distance (roundtrip): 3 km (2 miles)
Elevation Gain: Minimal
Precipitation: None
Temperature Range: -2 to 5 C (28 to 41 F)

On my trip to Burton Lake, I carried a similar pack with me to that of Hartley Lake, but this time I remembered my SynergyLink Connectors. The Connectors worked extremely well to keep my sleeping bag on my sleeping pad. I found that my sleeping bag stayed in position even after tossing and turning. The Connectors assisted a great deal with keeping the bottom of the sleeping bag (with less insulation) against the mat. I had a better sleep because I was not constantly feeling the draft of cold air against my back and trying to adjust the position of the sleeping bag. I found the connectors were a little tricky to set up and remove due to the loop and hook system. My cold fingers couldn't manipulate the loop and hooks very efficiently and I found myself getting frustrated after spending several minutes on one hook. See photos below of the loop and hook system and the SynergyLink Connectors connected across my sleeping pad.



I wore the same layers as I did on my Hartley Lake trip and felt a little warmer, which I attribute to both the use of the SynergyLink Connectors and the slight increase in the outside temperature.

Trip #4 Test Conditions and Performance
Location of Trip #4: Banff National Park, Alberta, Canada to Radium and Golden, British Columbia, Canada
Length of Trip: 3 days, 2 nights (May 19-20) 
Pack Weight on bike: 5 lbs
Pack Weight in support vehicle: 30 lbs
Distance (roundtrip): 320 km (200 miles)
Elevation: 2600 ft (800 m) to 5800 ft (1800 m)
Precipitation: None
Temperature Range: 4 to 25 C (39 to 77 F)

I used the Therm-a-Rest Questar sleeping bag on a 3 day 2 night supported road bike trip. I did not carry the sleeping bag with me on the bike as it was carried by the support vehicle, but I used it for 2 nights at the Radium and Golden campgrounds. The evening temperatures were around 4 degrees C (40 F). I wore a pair of fleece leggings and a long sleeve shirt to bed, and I tried wearing my hut booties but found my feet quickly grew too warm. I didn't use the bag's hood or foot pocket on this trip as it was too warm. With just the one layer of clothing and no extra socks, slippers, toque, or hood, I was the perfect temperature.

I found the sleeping bag very lofty and cozy. I especially looked forward to crawling into the bag after a long day of biking. It reminds me of my comfy duvet on my bed at home.

The SynergyLink Connectors were simple to hook up and unhook with warm fingers. I didn't notice the zoned insulation on this trip, with the exception of the foot area, as my feet seemed to grow warm very quickly.

I did notice a few more feathers escaped from the bag on this trip but have found no other issues thus far.


1. Sufficiently warm to at least -8 C (18 F)
2. Impressive water-resistant properties
3. Light-weight and packable
4. Hood fits snug with the drawstring
5. Very lofty and cozy

1. Zoned insulation feels cold when side-sleeping
2. No vents for breathability on warm nights
3. Mummy-shape not suited for side-sleepers as I cannot stretch out my knees
4. Hook and Loop system for the SynergyLink Connectors is difficult to manuever with cold fingers

Long-term Report

July 17, 2018

During the long-term test period I have taken the sleeping bag on one car camping trip and one backpacking trip. The car camping trip was located at Cross River Canyon Recreation Site east of Radium, British Columbia and the backpacking trip was situated close to Fernie, British Columbia. The backpacking trip was located in backcountry, mountainous terrain with vegetation typical of subalpine forest and alpine grasses and shrubs. We camped above treeline on the backpacking trip. Elevation ranged from 6200 ft (1900 m) to 9200 ft (2800 m). The car camping trip was at an elevation of about 3600 ft (1100 m).

Trip #5 Test Conditions and Performance

Location of Trip #5: Cross River Canyon Recreation Site, British Columbia, Canada
Length of Trip: 2 days, 1 night (May 25-26)
Pack Weight: N/A - Car camping
Precipitation: None
Temperature Range: 6 to 17 C (43 to 63 F)

I used the Therm-a-Rest Questar sleeping bag on a 2 day 1 night car camping trip before a trail race. We camped at Cross River Canyon Recreation Site which was a grassy and treed area close by the Kootenay River. The evening temperature was around 6 degrees C (40 F). I wore a pair of fleece leggings and a long sleeve shirt to bed. I didn't use the bag's hood or foot pocket again on this trip as it was too warm. I was really happy to find I was warm and comfortable throughout the night and had a great sleep.  I had no trouble staying on my sleeping mat using the SynergyLink Connectors.  I tried out the storage pocket on this trip and found it quite handy to store my headlamp in there for the midnight trip to the bathroom.

Trip #6 Test Conditions and Performance
Location of Trip #6: Heikos Trail near Fernie, British Columbia, Canada
Length of Trip: 2 days, 1 night (June 30-July 1)
Pack Weight: 25 lbs (11 kg)
Distance: 21 km (13 miles)
Elevation Gain: 4000 ft (1200 m)
Precipitation: Mix of heavy and light rain, hail at times
Temperature Range: 2 to 20 C (36 to 68 F)

I used the Therm-a-Rest Questar sleeping bag on a 2 day 1 night backpacking trip along Heikos Trail. I was extremely happy I had this warm sleeping bag because I was so cold when we finally finished the first day of hiking. We ran into quite a bit of rain and wind and I was cold enough that my fingers and toes were starting to feel numb. I had an "aha" moment when I was trying to warm myself up in the bag and couldn't get my feet warm. I was wishing I had brought an extra pair of socks or my hut booties. As I thought this, I remembered the sleeping bag has a foot warmer pocket! I stuck my feet in the pocket and my feet were toasty within minutes. I was surprised how quickly they warmed up. I think the foot warmer pocket is my favourite feature! The hood also helped to keep me warm throughout the night. I started off in several layers of clothing including mitts, toque, and down jacket, but within a few hours I was actually too hot and had to remove some clothing. One feature I miss in this sleepig bag is a stow pocket for my "pillow". By the end of the evening I was using my down jacket, toque and mitts for a pillow but it is difficult to keep the "pillow" in place without a stow pocket to keep it secure.

While eating supper, I spilled some sauce on the bag and found it easily wiped off with no staining.

I also tried carrying the bag in a new pack this trip, and found it easily fit into the sleeping bag compartment in the bottom of the pack.

At the end of this trip I checked for wear and tear and found 2 loose threads about 1-2 in (2.5-5 cm) long. Neither of them seemed detrimental to the functionality of the bag.


I really like this sleeping bag for temperatures between -8 and 6 C (18 and 43 F). At -8 C (18F) I found the bag to be on the cusp of not warm enough. Temperatures over 6 C (43 F) I would start to think about unzipping the bag, which still works fine, but means I could likely be using a lighter summer or 3 season bag instead. I do want to point out that I was using a 3-season sleeping mat for this test which likely affected my comfort level at the lower temperatures.

I was not a fan of the zoned insulation because I am a side-sleeper and found the zones with less insulation would feel very drafty when sleeping on my side. I did find that using the SynergyLink Connectors helped with this issue by keeping the zones with less insulation on or closer to the mat. My favourite feature of the bag was the foot warmer pocket which I found really helped warm up my feet quickly on several cold nights. The hood with drawstring was a close second favourite feature as it made it easy to keep the hood in place when I needed it. I was also very happy with the water resistance of the bag on the several occasions where it experienced a wet environment. Some features I would like to see added to the bag are vents for temperature regulation on warm nights, and a pocket for holding my "pillow" in place.

Besides the 2 loose threads and the occasional loss of a few feathers, I found no problems with the bag and would definitely consider it a durable bag.

1. Sufficiently warm to at least -8 C (18 F)
2. Impressive water-resistant properties
3. Light-weight and packable
4. Hood fits snug with the drawstring
5. Very lofty and cozy
6. Foot warmer pocket warms cold feet quickly (within minutes!)

1. Zoned insulation feels cold when side-sleeping
2. No vents for breathability on warm nights
3. Mummy-shape not suited for side-sleepers as I cannot stretch out my knees
4. Hook and Loop system for the SynergyLink Connectors is difficult to manuever with cold fingers.

Thank you Therm-A-Rest and for the opportunity to test this product. This concludes my reporting for this test.

Read more reviews of Therm-A-Rest gear
Read more gear reviews by Alyssa Kimber

Reviews > Sleep Gear > Sleeping Bags > Therm-a-Rest Quester 0 bag > Test Report by Alyssa Kimber

Product tested and reviewed in each Formal Test Report has been provided free of charge by the manufacturer to Upon completion of the Test Series the writer is permitted to keep the product. Owner Reviews are based on product owned by the reviewer personally unless otherwise noted.

If you are an avid backpacker, we are always looking for enthusiastic, quality reviewers. Apply here to be a gear tester.

All material on this site is the exclusive property of
BackpackGearTest software copyright David Anderson