Everything You Need to Know About Sleeping Pad R-Values
Hiking & Camping Expert Jessica LaPolla explains R-value—a common rating on sleeping pads—and how it should factor into your decision when choosing a pad!
There are a ton of different sleeping pads on the market for campers, hikers, and backpackers. They are diverse in their materials, intended use, and R-value. As an avid backpacker and hiker, I’ve always aimed to find a balance between warmth and weight in my gear, specifically in my sleeping pad. When I first started backpacking, terms like R-value and paragraphs about thermal resistance made my eyes glaze over. Not to fear, I’m going to take you through everything you need to know about R-values and how to optimize your sleep system and hopefully keep you awake in the process.
What Is R-value?
Let’s start with the basics—what exactly is R-value, and what does it have to do with sleeping pads? In simple terms, R-value is a measure of thermal resistance. Thermal resistance determines the heat insulation property in textile materials for sleeping pads. The higher the thermal resistance, the less heat is lost. Meaning the higher the R-value of your sleeping pad, the better it will insulate you and the warmer it will be. R-value is a tested measurement that depends on the type of fabrics or materials used, the thickness of the materials, and other qualities.
How Is R-Value Measured?
Most sleeping pad manufacturers use a thermally sealed container to test and measure the R-value of their sleeping pads. The pad is placed between two metal plates, which use sensors and are kept at a steady temperature using an electrical current. A pad with higher insulation or a higher R-value will keep the plate with the sensors warm, causing the sensors to use less energy. A pad with a lower R-value and less insulation will cause the sensors to use more energy to maintain the same temperature.
How Does This Affect Your Camping Experience?
Have you ever rolled off of your sleeping pad in the middle of the night and woken up from being too cold? This unfortunate night of sleep is due to a process known as conductive heat loss. The heat from your body is being transferred to the cold ground. If you’re having a hard time picturing this, think about a time you sat down on a cold metal chair. After a few minutes, the chair would feel warmer because of conduction.
Creating an insulating barrier between the sleeping pad and sleeping bag can prevent heat loss and keep you warm throughout the night. A complete sleep system made with the right materials can keep you warm in sub-zero temperatures.
How to Factor in R-value When Choosing a Sleeping Pad
Though higher R-values can provide more warmth in a sleeping pad, there may be circumstances when you want to choose a pad with a lower R-value. Typically you will see sleeping pads with an R-value between 1-7, with seven being the warmest. Sleeping pads with an R-value of 1-2 are good options if you plan on doing summer camping or backpacking, and are typically what you’ll see in most inflatable pads and air pads. R-values of 3-4 are great for three-season use. If you plan on camping through shoulder seasons or in winter, you will need a pad with a higher R-value, usually made of thicker foam materials.
Your sleeping bag temperature rating will also factor into what kind of sleeping pad you need to bring with you. For instance, if you have a bag rated to 0-degrees Fahrenheit and plan on camping in 40-degree temperatures, you have some wiggle room when choosing a sleeping pad. Vice versa, if you have a sleeping pad with an R-value of 6.5, you may not need to bring that heavy 0-degree bag and could get by with a lighter one.
Generally, you will want to err on the side of caution and pack on the warmer side, especially if you are expecting chilly conditions. You can constantly adjust your gear on future hiking trips based on how you slept, especially for cold sleepers. It is much easier to cool down in the night by unzipping your bag or taking off a layer than it is to warm up because you didn’t pack the right gear.
Sleeping Pad Recommendations
These are some of my favorite sleeping pads. These comfortable pads will keep you warm and cozy in the backcountry, with something for every season, from ultralight backpacking to winter car camping.
Sea to Summit Ultralight Sleeping Pad
At 13.9 ounces, this ultralight sleeping pad weighs less than a roll of paper towels and packs down smaller than one as well. It has an R-value of .7, idealizing summer/warm weather backpacking. Despite the minimalist design, this pad uses an integrated inflating device to give you four inches of cushioning and protection from the cold ground. Ripstop nylon increases durability and prevents leaks and punctures but does come with a repair kit in the event of a tear. If you want to increase your warmth with this pad, pair it with a light closed-cell foam pad or use a warmer sleeping bag.
Therm-A-Rest Basecamp Sleeping Pad
This self-inflating open cell foam pad with an R-value of 6 will keep you warm and comfortable during cold weather camping. At 2.8 pounds, this pad is best used for car camping or base camping but could be used for winter backpacking as well. The valve system allows for easy inflation and easy deflation, saving you time at camp.
Nemo Tensor Alpine Sleeping Pad
The Nemo Tensor insulated sleeping mat balances warmth, weight, and comfort impressively and effectively., This lightweight pad has an R-value of 4.8 and a temperature rating of -20 degrees Fahrenheit, and weighing in at 1 pound 4 ounces, it is perfect for winter backpacking or mountaineering. It is also comfortable enough for car camping. The stuff-sack doubles as a pump, making it super easy to inflate.
Many variables contribute to the warmth and efficiency of your sleep system, and R-Value is often overlooked despite its importance. Some trial and error may be necessary when selecting a sleep system that works for you, but hopefully, this article has highlighted a few key points to consider when shopping. If you have questions about R-values, sleeping pads, or need help choosing a new sleeping pad that is right for you, reach out to a Camping & Hiking Expert here at Curated. We will help you choose the best sleeping pad and create the perfect sleep system based on your needs.