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A sub-zero sleeping bag, also known as a cold weather sleeping bag or zero-degree sleeping bag, is designed to keep you warm when the thermostat drops below the freezing mark. The warmest sub-zero bags can protect you from temperatures as low as -40 degrees Fahrenheit. When you’re camping in extreme cold, it’s not just a matter of comfort but survival also.
Sub-Zero Sleeping Bag FAQs
How do sub-zero sleeping bags work?
Sub-Zero sleeping bags have several design features to stay warm when the temperatures drop. Mummy-shaped bags offer the most snug fit. Unlike regular sleeping bags, sub-zero bags are often down-filled, the warmest type of insulation. They also tend to have shorter zippers because the zipper is where the cold air gets in. A down-filled, mummy-shaped sleeping bag with a short zipper is designed for maximum warmth.
Is a zero-degree sleeping bag too warm?
Sub-zero sleeping bags are not meant for warm-weather camping. If you’re using one during a hot summer night, unzip the bag to allow the air to flow. You’ll probably want to purchase a regular sleeping bag and keep your cold-weather bag for use during the other seasons.
How much does a sub-zero sleeping bag cost?
Generally speaking, cold-weather sleeping bags are pricier than regular sleeping bags. This is due to their more durable construction, with heavier zippers and added insulation. But like anything else, you can find bags at different prices to cover a range of budgets. For example, our Sub-Zero Sleeping Bag Buying Guide features bags priced below $100 on the low-end and well over $300 on the high-end.
Do sleeping bag liners help?
Sleeping bag liners are a great way to add warmth without purchasing a warmer bag. However, if you’re camping in extreme cold, adding a sleeping bag liner to a sub-zero sleeping bag is likely not necessary. Here are six of the warmest sleeping bag liners on the market today.
Is a zero-degree sleeping bag too warm?
A sub-zero bag can feel too warm if you’re using it during summer. You can unzip a zero-degree bag and use it as a blanket if needed. It will help keep you cool, but you still might find yourself overheating. If it’s sweltering, you won’t even use a sleeping bag.
What is the coldest-rated sleeping bag?
While no brand can claim the title of the coldest-rated sleeping bag, any bag rated to -40 degrees Fahrenheit will keep you warm at almost any temperature you will encounter, even if you’re camping in the winter.
Can a sleeping bag still keep you warm when it’s wet?
If your sub-zero sleeping bag gets wet, all bets are off. As long as the water doesn’t soak through, you may be okay, but it will be tough to stay warm in the cold if you get wet. Something worth noting is that while down-filled bags are warmer than synthetic insulation, they don’t perform as well in damp weather.
Do they make heated sleeping bags?
Heated sleeping bags contain electronic heating pads that connect to a USB-powered heating supply, like this bag from Mantuole. You will need a power supply, which may or may not be practical depending upon where you’re camping and how long you plan to be off-the-grid if that’s the case.
How can I increase the warmth of my sleeping bag?
Before purchasing a sub-zero sleeping bag, I recommend adding a sleeping bag liner, as it’s the more economical choice. However, if you plan to camp regularly when the temperatures drop below the freezing mark, a sub-zero sleeping bag is worth the investment.
