With winter approaching and you have a few ideas for some winter camping outings, one thing you will want to consider when buying accessories is the R-value of the product. The rating can be found on camping equipment such as sleeping pads, tents, and some clothing. The value rating determines just how warm you may be when camping in very cold and below zero temperature conditions.
R-Value For Winter Camping – What Do I Need To Consider?
When you are planning a winter camping adventure, and you need to buy new or additional accessories, check the product description. With the R-value information in hand, you will know how well the product will hold up to cold temperatures. You will want to know the R-value of a product before heading out into freezing cold terrain to be sure you have the right product for winter camping versus a product suited for other times of the year.
The easiest way to define R-value is to say that it rates (values) how efficient the insulation used in a product is at blocking the flow of heat. In other words, does the insulation keep the heat in and keep the cold out is the question you want an answer to when selecting winter camping gear.
The type, density, and thickness of the insulation material is how the R-values are determined. Along with camping gear, the R-value is also used in construction when insulating a building, and for mattress manufacturers, scientists, and engineers.
In technical terms, the R-value determines (measures) the thermal resistance of a structure or material. The higher the R-value a product has, the more thermally resistant the structure or the material is. Expect higher R-values to be more expensive.
What R-Value Is Enough? (And R-Value Stacking For Extra Warmth)
Think about winter attire. To stay warm, we put on several layers of clothing, such as a base shirt, flannel shirt, sweater, then a jacket. This is known as stacking. The same process is used for winter camping.
When preparing for winter camping, the accessories you use can be stacked. For example, stacking two R-value sleeping pads that are rated at 5 increases warmth close to 10. There is a minor decrease in the R-value when stacking products due to retention.
For winter camping, an R-value of “5” overall is recommended for sleeping pads, but an R-value of “3” may be all you need, depending on the temperature and if you use stacking. For your clothing and a tent, select products with a higher R-value.
To ensure you stay warm, especially if the temperature drops to extreme levels, have extra sleeping pads available so you can stack them and increase the level of insulation.
Two of the same type (inflatable or foam) sleeping pads can be stacked together. To reduce the chance of the pads slipping due to their slippery surface, put one inflatable sleeping pad in place, then set a foam sleeping pad on top of it followed by the sleeping bag. This setup provides comfort plus versatility.
Do Sleeping Pad R-Values Matter?
To prevent cold and sleepless nights, a sleeping pad is a necessary companion for your sleeping bag. Without the aid of a sleeping pad, once you get into your sleeping bag there is no insulative layer of protection from the cold ground. The coldness of the ground coming in contact with the warmth of your body results in conductive heat loss. With an R-value sleeping pad, this is eliminated, resulting in a warm and comfortable sleeping time.
When setting up your sleeping system for winter camping, take into account the warmth provided by an R-value sleeping pad along with the warmth provided by the temperature rating of the sleeping bag to ensure your system can keep you warm when the temperature dips into the low teens, or below zero.
How Are R-Values Measured?
Before 2020, no standardization for measuring R-values was in place. This meant companies were using various systems to establish the R-values for their products. This included companies using independent and third-party researchers, companies doing their own in-house testing, and others that simply estimated the R-values. For some companies, using a temperature rating system instead of an R-value was used on their products.
In 2020, ASTM International put into place a standard for product R-values that provides consumers a way to compare products such as sleeping pads. The system is similar to the EN.ISO temperature rating system.
High R-Value Products
As mentioned, there are several things you will want to have for winter camping that have either a high R-value, or you have access to multiple accessories that allow you to use the stacking method to reach high R-values.
Below are examples of some of the products to consider.
The R-values for sleeping pads vary for different seasons. The values can range from R2, which is minimally insulated, to R5.5, which is considered to be well insulated. The general R-value range for sleeping pads is 1 – 3 for summer camping, 3 – 5 for spring and fall camping, and 4.7+ – 5+ and higher for winter camping.
- REI Co-op Flash Thermal – Dual-fiber insulation – R-value: 4.7
- Nemo Tensor Alpine – 20-degree Fahrenheit rating – R-value: 4.8
- Therma-a-Rest NeoAir XTherm – Pad thickness of 2.5 inches – R-value: 6.9
Most, not all, manufacturers of sleeping bags use the EN (European Norm) or ISO (International Organization for Standardization) system to rate sleeping bag warmth. Instead of an R-value listed on the product description, you will see a temperature rating that the sleeping bag can endure. Some companies prefer to do their own testing to determine temperature ratings instead of using the standardization protocol of EN/ISO.
It is important when buying a sleeping bag that it be paired with an appropriately rated R-value sleeping pad for optimum warmth during winter camping. Also, keep in mind that the shape, size, roominess, and features of the sleeping bag play a role in finding the right balance between it and the R-value sleeping pad.
A few examples include:
- Kelty Cosmic Ultra O – 0F and below – Down
- Kelty Kush Sleeping Bag – 30F – Synthetic
- Marmot Warmcube Gallatin Sleeping Bag – 20F – Down
- Western Mountaineering UltraLite – 20F – Down
A tent with an R-value can increase the comfort level while camping during the winter. These tents are available for 2 to 6 campers and may have a single room or multiple rooms.
Several tents to consider include Crua Loj 6, Crua Tri 3 Insulated Tent, and the Crua Cocoon Insulated Dome Tent. The Loj 6 and Tri 3 have an R-value of 4. The Loj 6 and the Tri 3 have an R-value of 4. The Crua Cocoon has an R-value of 9.
There are many factors to consider when setting up a winter camping system. Not only is the location of where you will be camping a factor, you must also consider the type of terrain you will be sleeping on (dirt, rocky soil, frozen ground, etc.), the potential temperature, and gear that is value or temperature rated.
To ensure warmth and comfort in frigid conditions, do thorough research, check product descriptions for ratings, read customer reviews, and contact the manufacturer directly if you need more information.