Anytime you go tent camping or backpacking, a sleeping bag is necessary for both comfort and warmth. When temperatures drop, it can be the one item in your gear, other than shelter, that can save your life.
Not only that, but it can ensure you get a good night of rest so you can continue hiking or enjoying other activities the next day. If you aren’t warm enough, your sleep will be interrupted or you may have difficulty falling asleep at all.
Although you may own a sleeping bag, to maximize its warmth, you may want to insulate it even further. So how can you insulate your sleeping bag?
One of the best ways to get the most insulation from your bag is to start with a very warm, down-filled bag and pair it with a high-quality sleeping pad.
Which Sleeping Bag Fillings Provide the Most Insulation?
Most sleeping bags have either a natural or synthetic filling for insulation. Natural fillings include down which can come from geese, ducks, or other kinds of waterfowl. Synthetic means artificial insulation that is often polyester, Thermolite, Hollofil, Quallofil, or PolarGuard.
Down filling is often considered superior to synthetic because it is natural and comes from the down of animals. This material does not actually consist of feathers.
Instead, it is the plumage that is underneath the feathers and works to insulate and keep their bodies warm. It is lightweight, making it perfect for backpackers, and very compressible so it won’t take up a lot of space in your pack.
Goose down is also quite warm and is often used to fill four-season sleeping bags that can withstand sub-zero temperatures. The only drawback is that goose down is not insulating when wet.
However, if you want the most warmth and insulation, look for a sleeping bag that is filled with down. The fill rating will tell you how much down is inside the bag and a higher number means more insulation.
Adding Extra Down for More Insulation to your sleeping bag
Although it can be difficult to add down filling to an existing sleeping bag, this might be an option if you think your sleeping bag is not warm enough. Depending on the design of the bag and whether it has inside baffling to disperse the down, you may be able to add more insulation.
Because down can easily shift around or clump together inside a bag, usually there are small compartments sewn into the bag to ensure insulation is balanced. This can make the bag hard to fill with extra down.
If you would like to get more down added, the best option is to contact the manufacturer and see if they can make adjustments. You can also contact a company that specializes in camping gear who can open the baffles for you and add more down.
How to Add More Down to Your Sleeping Bag
Should you choose to take on the task of adding more down yourself, there are a few steps to follow. First, you will need to purchase the goose down fill stuffing which can be found online.
Look for high-quality down that comes from European countries where the geese are allowed to mature before the down is harvested. This will ensure large clumps of down that have a lot of fill and will be very insulating.
You can also use the down from old sleeping bags that are no longer warm enough. If you have a few lying around the house, unstitch them and take the down from inside. Then turn your sleeping bag inside out so you can see the seams inside. This will also ensure that any restitching is not visible in case it is not perfectly done.
If there are baffles, you will have to find the seam where each tube is sewn shut. Then, using a seam remover, start to gently lift the stitches away. Make an opening large enough to fit your hand inside and slowly pull the tube open. Then start stuffing it with down.
Don’t overstuff the baffle either and, instead, ensure that enough space is there so you can fluff up the down and get more loft inside. Then carefully stitch the tubes back up and make sure the seams are tight so down will not leak out when the sleeping bag is used again.
Refilling your sleeping bag with down can be a time-consuming and messy process. Down is lightweight and can easily leak out and float away. To make the task a bit easier, portion out the down before stuffing the bag. Put a set amount into a small bag or envelope and, once the baffles are open, pour the down inside so it doesn’t make a big mess.
How to Use a Sleeping Pad Properly And Stay Warm
If your sleeping bag has already been filled with extra down or, if it’s brand new and still has plenty of loft, there are other ways to add more insulation. The most common way to insulate a sleeping bag is to add a sleeping pad.
The sleeping pad is placed underneath the bag and acts as a barrier between the bag and the cold ground. Sleeping pads can be filled with air or made from closed-cell foam. For the most insulation, choose a self-inflating sleeping pad because they have a combination of both air and foam. When you open the valve, the chambers will be filled with air.
Because they also contain open-cell foam, they provide a lot of insulation. Some sleeping pads also have down insulation and are designed for sleeping in very cold places. Like sleeping bags, many sleeping pads are also rated with a specific R-value. Look for an R-value of 4 for the most insulation.
By putting a sleeping pad under the bag, you will have a layer of warmth so the cold temperature of the ground will not come through and chill your back. The air inside the sleeping pad doesn’t conduct energy very well so heat loss will be significantly slowed by surrounding the body with air.
Other Techniques for Adding Insulation to Your Sleeping Bag
Getting a high-quality sleeping bag and the correct sleeping pad will go a long way toward providing the most insulation possible. But, if you want even more, there are some ways to keep adding warmth.
- Fluff up the down
Wash your bag and let it dry thoroughly so the down is cleaned. Then, declump any areas that are stuck together and shake the bag. This will restore loft to the down and make it insulate even better.
- Add blankets on top and underneath
Bring some extra blankets along if you are car camping and can easily transport them. Fold a blanket several times and put it down on top of the sleeping pad. Then add a few blankets on top of your sleeping bag once you are inside for even more warmth.
- Double up
Use two sleeping bags at one time by climbing inside one and then using the other as a blanket draped over the top, or putting the first bag inside the second. You can also double up on sleeping pads by adding a closed-cell foam pad underneath your self-inflating pad.
- Make sure your bag fits
If there is a lot of space between you and the sleeping bag, your body heat will escape and fill that area. One of the reasons sleeping bags work is because they trap this warm air close to your body.
But, if your sleeping bag is too big, then you won’t benefit from the warmth. So get a bag that fits your body and is snug enough to trap the air without being too constricting.
- Get a mummy bag
One of the warmest shapes for a sleeping bag is the mummy style. It is designed to fit the contours of your body and is narrow through the legs. It will close snugly over your head too so there are no gaps for cold air to get inside.
- Dress appropriately
Don’t expect your sleeping bag to do all the work for you. You can help it keep you warm by wearing layers and ensuring you have long sleeves and long pants on. Add in socks and also make sure the clothes are dry before getting into the bag.
- Add a liner
Get even more insulation by adding a sleeping bag liner to your bag. Find one that is made from fleece or Thermolite and you can add up to 30 degrees of warmth. This adds an extra season to your sleeping bag and it can also be used by itself.
- Get warm first
Make your body as warm as possible before you get inside the sleeping bag. If you start with a warm body, once some of the heat is lost, you will still be warm. Spend time near the campfire, drink a hot beverage, or eat a warm meal to heat up.
Add in some chemical warmers or put on a hat and gloves so you are nice and toasty. Then crawl in the sleeping bag and, if you start to overheat, you can remove a few layers as the night progresses.