Therm-a-Rest® Sleeping Bags - FAQs

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How do Therm-a-Rest® sleeping bags offer a better way to sleep in the outdoors?

Therm-a-Rest® sleeping bags offer a lighter, more comfortable way to sleep. Using an integrated system approach that pairs mattress and pad together, our system solution also allows our bags to be among the lightest on the market, making them an ideal choice for anyone in search of warmer, more restful nights and lighter, more productive days in the backcountry. Read more about our Design Philosophy.

Do I have to use a Therm-a-Rest® pad with my Therm-a-Rest® sleeping bag?

No. Our SynergyLink system that connects your bag and mattress together works with any pad up to 25” wide. We recommend Therm-a-Rest® NeoAir mattresses, especially the XTherm, All Season and XLite, because they are incredibly light and warm. They also provide reflective warmth you can feel through the bottom of our 3-season bags. Self-inflating mats and closed-cell mats also work well for customers who don’t have a Therm-a-Rest® NeoAir mattress.

Like many sleeping bags, Therm-a-Rest® sleeping bags are tested and rated when paired with a mattress with an R-value of approximately 4.7, where R-Value is a measurement of the warmth of the mattress. This R-value is clearly marked on all Therm-a-Rest® mattress packaging and on our website. As long as you use a mattress with this R-value or higher, most people will be warm at the advertised temperature rating for any of our bags.

Everyone sleeps differently in the outdoors, and you must ultimately find the combination that works best for you. If you are a warm sleeper, or are using a bag that has a temperature rating significantly higher than the temperature you are sleeping in, you may be comfortable with a lower R-value mattress. Alternatively, if you sleep cold, or have a bag that has a temperature rating significantly lower than temperature sleeping in, you may prefer to use a higher R-value pad.

What kind of testing went in to the development of Therm-a-Rest® sleeping bags?

For over 40 years Therm-a-Rest has pursued a single mission: to provide the best night of sleep in the outdoors. Along the way, we’ve spent countless hours field testing, conducting independent trials and studying consumer feedback. And we are one of the only manufacturers in North America with an in-house cold chamber. For close to 20 years, we have tested sleeping bags and mattresses together in our cold chamber and examined almost every aspect of sleep insulation to better gauge real world performance.

We have always approached product testing with the view that the mattress and sleeping bag need to function together as one system to provide optimal comfort and performance. Through our decades of research, we have learned exactly what makes a great night under the stars.


Why are Therm-a-Rest® sleeping bags so great for slide sleepers?

Research shows that almost seventy percent of people sleep on their side, thirteen percent sleep on their back, and only seven percent sleep on their stomach. Unlike most mummy bags that are designed for people who sleep on their back, Therm-a-Rest® sleeping bags are designed to accommodate a wide range of sleep positions.

Therm-a-Rest sleeping bags are designed with extra room in the torso to allow your shoulders, elbows and hips to move freely. At the head and foot the fit is closer, keeping you warm and decreasing overall weight. Our Efficient Comfort design is ideal for side sleepers or anyone who wants more freedom of movement without adding extra weight to their pack.

How do I insert my pad into the SynergyLink Connectors attached to my sleeping bag?

Our patent-pending, easy-to-use connectors ensure that you stay on your pad, so you can stay warm all night. To insert your mattress, start with a fully inflated pad. Insert the head of the pad into the fabric connector near the head of the sleeping bag, then bend the pad and insert the foot of the pad into the other connector.

How do I attach my Alpine or Regulus blankets to a mattress?

The Mattress Loop Kit, now included with each new blanket, and sold separately in the Fast & Light Mattress Snap Kit, includes (8) loop tabs with adhesive backing that let you attach your Therm-a-Rest blanket directly to any mattress, creating a lightweight sleep system.

Can a Therm-a-Rest® NeoAir mattress really make my Therm-a-Rest® sleeping bag feel warmer?

Unlike other mattresses, Therm-a-Rest® NeoAir mattresses reflect a moderate amount of radiant heat. When used next to the skin, the effect is noticeable. Although this radiant heat always contributes to overall warmth, most sleeping bags have too much insulation in the back for the effect to be noticed. Therm-a-Rest® sleeping bags are designed with less insulation in the back than most other sleeping bags, allowing radiant heat to be felt throughout the night.

How do I connect my Therm-a-Rest® bag to another sleeping bag?

We don’t recommend zipping two mummy bags together – it doesn’t result in a great sleep experience. There are a variety of preferred systems available for shared sleeping, including Therm-a-Rest® blankets, which provide greater comfort and freedom of movement.

If you do choose to connect our bag to a bag from another brand, look for a bag with a right-facing YKK #5 zipper of a similar length, sewn with the coil facing the inside of the bag. This is combination is relatively common among competitor’s bags. We are only offering Left zipper configurations at this time.


What is Zoned Insulation?

Our Zoned insulation puts loft where it helps you the most, so you can sleep warmer. Fill is concentrated in the top of your sleeping bag, where it traps rising warm air. The bottom of the bag is insulated by your mattress and requires considerably less fill to keep you warm. Our construction is based on thermal mapping and supported by over 40 years of sleep research. Read more about our Design Philosophy.

What is Eraloft synthetic insulation?

Therm-a-Rest® sleeping bags use a unique synthetic insulation that incorporates the best characteristics of both short and long staple insulation. Our EraLoft synthetic insulation uses three distinct fibers to create a structure that is lightweight, compressible, warm and durable. The hollow fibers are highly resistant to water and provide warmth even when wet. The insulation is built into Therm-a-Rest® sleeping bags using shingle construction, a configuration that minimizes heat loss and provides the most efficient performance.

Is the goose down used in your insulation humanely sourced?

Therm-a-Rest actively supports industry-wide efforts to ensure all down-filled products are made with the least harm possible. We are opposed to inhumane practices and actively work with peers across all industries to improve the treatment of geese. Our product development team plays an active role in the Outdoor Industry Association (OIA) and its Textile Exchange Materials Traceability Working Group (TEMTWG). Our team also serves on the TEMTWG Down Task Force, working to address key issues in the down and feather industry and manufacturing supply chain.

To learn more about OIA Working Groups visit:

Care & Use

What should I do if my sleeping bag loses down?

It is unusual, but occasionally a down plume can pass through the fabric of any sleeping bag. The best solution is to cut the down plume as close to the fabric as possible with a pair of scissors. This removes the sharp end of the plume that managed to penetrate the fabric. Then, push the remainder of the plume back into the bag. Rub the fabric between your fingers to seal the hole. Most sleeping bags hold more than two million down plumes. The loss of a handful will make no difference in your sleeping bag’s performance.

How do I store my sleeping bag when not in use?

Sleeping bags must be stored dry and loose (not compressed) in order to extend the life of the bag. All Therm-a-Rest® sleeping bags come with a Compartmental Storage Sack. For long term storage, the sleeping bag should be stored with the sack fully extended. For short-term storage or when shipping, you can use the smaller draw cord loop in the center of the sack to create a tighter container that saves space.

How do I clean my Therm-a-Rest® sleeping bag?

Follow the care instructions below to help maintain the high quality and extend the life of your down or synthetic Therm-a-Rest® sleeping bag.

Down Care Instructions:

  • WASH: Hand wash or machine wash in large capacity, front loading washing machines. Use a mild, non-detergent powdered soap or special down soap. Select cold water and a gentle cycle with two rinses.
  • DO NOT dry clean. DO NOT bleach. DO NOT iron.
  • DRY: Tumble dry in large commercial dryer on low heat, checking often to redistribute down and to check for overheating. Look for clumps of wet down and shake bag gently to redistribute down.
  • DO NOT use your home dryer (which may melt the fabric). DO NOT hang dry. DO NOT store compressed.
  • STORE: Storing your sleeping bag loose in a cool, dry place can extend the life of your bag.

Eraloft Insulation Care Instructions:

  • WASH: Hand wash or machine wash in large capacity, front loading washing machine. Use a mild, non-detergent soap. Select cold water and a gentle cycle with two rinses.
  • DO NOT dry clean. DO NOT bleach. DO NOT iron.
  • DRY: Tumble dry in large commercial dryer on low heat, checking for even distribution of fill material. Gently massage the bag to eliminate any bunching.
  • DO NOT use your home dryer (which may melt the fabric). DO NOT hang dry. DO NOT store compressed.
  • STORE: Storing your sleeping bag loose in a cool, dry place can extend the life of your bag.

Service & Repair

What if I want to return a Therm-a-Rest® sleeping bag?

Our Better Sleep Guarantee ensures that if you are not completely satisfied with your Therm-a-Rest® sleeping bag, we will give you a full refund – no questions asked. Return your clean, undamaged bag or blanket to the place of purchase within 90 days, with your original receipt, and receive a full refund. If your retailer is not participating, please contact Therm-a-Rest directly. Learn more about our Better Sleep Guarantee.

What is the Therm-a-Rest® Warranty policy for sleeping bags?

Therm-a-Rest® offers a Limited Lifetime Warranty for most products including all sleeping bags. Your sleeping bag is guaranteed without time limit against defects in materials and workmanship. We also offer repair services for damages not covered under warranty. Learn more about Therm-a-Rest® Warranty & Repair.

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