Camping can be such a fun activity, but camping in the rain can lead to some soggy gear. If your tent doesn’t block out all of the water, will you be left sleeping in a puddle, or will your sleeping bag protect you?
No sleeping bag is completely waterproof—if they are left in water they will get wet. There are some sleeping bags that have a water-resistant outer layer, and bags can also be covered by a waterproof sack or coating. With preparation, a sleeping bag can be used in any type of situation, wet or dry.
Whatever your situation is, nobody wants to camp with a soaked sleeping bag. Here are some things that you should know so you can prepare yourself and your bag.
Different Types of Sleeping Bags
While no sleeping bag you find at the store or online is going to be truly waterproof, not all sleeping bags are created equal. There are two main types of sleeping bags: those with a water-resistant outer layer and those without that layer. We will explore what each of these bags is and what they mean for you.
Some sleeping bags come with a water-resistant outer layer. While this can be called a variety of things, common names you might hear thrown around are Gore and Pertex. Both of these are synthetic materials that are made to be water-resistant. You can commonly find them in raincoats and shoes, not just in sleeping bags. When water hits this material, it will bead up and slide off of the bag, preventing the droplet from soaking into the bag. While this prevents your sleeping bag from becoming soaked, it causes other issues.
While it is nice to have a layer that prevents water from coming in from the outside, this layer can become a double-edged sword. An important trait for a sleeping bag to have is breathability. This is important because, as you sleep, your body will release moisture through your breath and sweat. Normally this vapor is able to soak through the bag and escape once it hits the outer layer. However, with a water-resistant layer, this moisture is trapped in the bag with you. The lining of your bag will get cold and wet with no way to dry out. In cases like this, it might be better to look for a bag with more breathability.
The second type of sleeping bag is one that focuses on breathability. These bags will not have a stiff outer layer like the water-resistant sleeping bags. Instead, they will use a shell layer that covers the lining while still letting air pass in and out. A weakness of this type of sleeping bag is the amount of water they could let seep into the bag with you. While they aren’t the best for wet situations, they are an excellent type of bag for most other types of camping. If you want a bag that specializes in keeping water out, you will want to look for a water-resistant bag. If instead you want a more flexible bag, you’ll want to look at a bag with more breathability.
If you are interested in flexibility, you may be interested in a Bivy Bag. Bivy Bags or “Bivouac sacks” are an alternative to tents that can be used to keep a sleeping bag dry. Essentially what they are is a layer of waterproof material that a sleeping bag can be placed inside. The sack can be tightened to keep water, dirt, and bugs from getting inside your sleeping bag.
Unlike a water-resistant sleeping bag, the sack is a separate layer from the sleeping bag. This allows for more breathability and a path for water to escape past the waterproof fabric. The sack can be used with a tent or in place of a tent. This is an excellent option if you want the greatest amount of flexibility with your equipment. By using a Bivy sack, you can use a breathable sleeping bag even in wet conditions. Once it dries, you can just use the sleeping bag. When the conditions are right, some campers ditch their sleeping bag and just use a Bivouac sack for cover.
How to Waterproof a Sleeping Bag
On the other hand, you might not want to buy and carry around another piece of equipment with you while you are camping. In that case, you might be wondering if you could just waterproof the bag that you already have. This is a viable option, but here are some things to keep in mind before running off to the store.
Is your bag already water-resistant? If it is, treating the outer layer with more chemicals is unlikely to improve its ability to repel water. If instead, you have more of a breathable bag that you want to secure, this may be the option for you.
Simply purchase a spray-on waterproofing product, such as the Nikwax TX-direct spray, follow the instructions, and voila! You have a waterproof bag!
Something to keep in mind, by increasing the water-resistance of the bag you are decreasing its breathability. This can be of particular concern if your bag has a natural lining, like down, which needs to be kept as dry as possible. If you are happy with how your sleeping bag feels, it may be better to avoid treating it and simply carry a cover or sack for the bag next time you go camping. (Source)
How to Pack a Sleeping Bag
When you pack your sleeping bag, you want to make sure that it won’t get wet before you’re even using it. There is nothing worse than spending all day traveling just to jump into a soaked sleeping bag. To keep your bag dry, you’ll want to make sure the pack you are carrying it in doesn’t have any holes or ways for water to slip in. Your bag can be kept inside a carry sack or your bivy bag if you bringing one along. The video below explains a simple way to use a garbage sack to pack your sleeping bag as dryly as possible.