We often get questions about the temperature ratings of our sleeping bags and quilts. In this article, we hope to answer some of these questions to help you make a more informed purchase.
Have your sleeping bags been EN tested?
The EN/ISO testing standards were developed in Europe and are used to standardize the temperature ratings for sleeping bag ratings. Although helpful in comparing sleeping bags between manufacturers and selecting an appropriate sleeping bag for specific conditions, EN/ISO standard testing is a fairly involved process that requires significant resources. As a result, it is beyond our means at this time. Since we are still a small company, we have decided to dedicate our limited resources to product development and offering great value to customers. We do plan to get EN/ISO ratings testing done in the future.
How do you determine the temperature ratings of your sleeping bags?
We have used various other factors to determine our reported temperature ratings. This includes measurements of the amount of loft our sleeping bags generate, comparison to other rated sleeping bags on the market, and extensive field testing at various conditions here in Colorado. We've also relied on customer feedback over the years. Many customers who have used our sleeping bags at various temperatures have provided very positive feedback and confirmed that our ratings are accurate.
The high amount of loft is what helps our Thermodown 0 sleeping bag achieve a 0°F / -17°C rating.
Are your ratings for comfort or risk/extreme?
We would consider the reported ratings to be the "comfort limit", which means that it's the lowest temperature where someone might be comfortable in a relaxed position. It's not the "risk" or "extreme" rating at which someone might be in danger of hypothermia. This limit would be much lower.
However, since comfort is subjective, it does depend a bit on how tolerant someone is of the cold. If you consider yourself a "cold sleeper", then we'd recommend adjusting the rating by 5-10 degrees to provide a more reasonable rating.
What about quilt temperature ratings?
Quilts are a bit more difficult to rate, as there are currently no industry standards. This is due to a lot more variables coming into play with quilts. First, quilts only provide partial coverage as opposed to being fully enclosed like in a sleeping bag. Quilts also don't have any hoods. Finally, since a quilt doesn't typically insulate underneath (either due to lack of tucking the quilt in or the filling material being compressed), the sleeping pad that is being used becomes a critical factor in how a quilt will perform.
Backpacking quilts are very versatile pieces of gear, but their lack of a hood and partial coverage mean that they don't sleep quite as warm as a traditional mummy sleeping bag.
We determine our quilt's temperature rating similarly to how we rate our sleeping bags, primarily by measuring the amount of loft that the quilt generates (i.e. how thick the down filling is when the quilt is laid flat). This is how many quilt manufacturers rate their quilts. Specifically, we use the following chart to help develop our ratings:
- 10 degrees – 3.0 inches
- 20 degrees – 2.5 inches
- 30 degrees – 2.0 inches
- 40 degrees – 1.5 inches
As an example, our Thermodown 15 quilt lofts to about 3 inches when laid flat, which translates to a temperature rating of around 10 - 15 degrees Fahrenheit.
In addition, we have once again done extensive field testing of our quilts to confirm these ratings. Customer feedback has also been very positive, with most customers reporting that the rating is accurate.
What other factors play into sleeping bag temperature ratings?
In addition to the design and specifications of a particular sleeping bag, there are other factors that will influence the comfort of a sleeping bag or quilt. This includes the type of clothing you are wearing and whether the clothing is effective in wicking any moisture away from your skin. One very common experience is being warm early in the night which causes moisture and sweat to develop. As temperatures drop during the night, this moisture can cause discomfort and a "cold" feeling. As a result, it is important to wear moisture-wicking base-layers and trying to prevent any sweat from developing during the first part of the night. Leaving your sleeping bag or quilt a bit open to maintain a comfortable temperature early on can really help and ensure more comfort later when temperatures get colder.
An adequate shelter can also be important. It's not uncommon for a well-insulated tent to be 10 to 20 degrees warmer inside than outside temperatures. When using a mesh bivy or tarp, this extra insulation will not be present and will require a sleeping bag or quilt with a lower temperature rating to be comfortable.
Finally, an adequate sleeping pad with a sufficiently high R-value is critical. Sleeping bags and quilts will not provide great insulation from the ground since much of the filling material is compressed and the air space that the fill needs to provide insulation will not be present. As a result, the pad will be the primary insulation from the ground and should be carefully selected for the specific conditions that will be encountered.
Which sleeping pad R-value do I need?
This will mostly depend on what time of year you will be using your sleeping pad and whether or not you'll be visiting high altitudes. We encourage you to do some research on the types of overnight temperatures that you'll be expecting. If you'll be at high altitudes, there are several websites that can provide good estimates of overnight temperatures on the actual peaks. Once you've done your research, you can make a decision about the right sleeping pad.
As a general rule, here are sleeping pad R-values for each season:
- Winter - 3.0 or higher
- Spring/Fall - 1.0 to 2.5
- Summer - 0.5 to 1.5
It is also worth noting that women and cold sleepers will usually need a higher R-value, so we'd recommend adjusting the above by 1 point. High alpine conditions with low overnight temperatures will also need an adjustment.
We hope this article has answered your questions about our temperature ratings as well as given you some insight into making an informed decision. If you have any other questions, feel free to email us at support@pariaoutdoorproducts.com or leave us a comment below.
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