Compression Sack Sleeping Bags – How Long Can They Stay Compressed?

Sleeping bags can be hard to store and fold away without already being rolle dup and stored in a compression sack. This makes them much smaller, easier to store and gives them a protective layer.

There is no designated time which you should or shouldn’t keep your sleeping bag in a compression sack. If you plan to leave your sleeping bag in a compression sack for longer than a few days you may notice the loft is thinner and not as warm when you next use it.

In this article we are going to talk about the different benefits of using a compression sack for a sleeping bag, what to do before you store your sleeping bag in a compression sack and how long you should be leaving your sleeping bag in a compression sack.

Do Sleeping Bags Come With Compression Sacks

Not all sleeping bags come with compression sacks, but you will be able to store almost any sleeping bag in one. You will find compression sacks to fit most sleeping bags whether yours came with one or not.

There are advantages to storing your sleeping bag in a compression sack, space-saving to mention one, however, there are disadvantages too. A sleeping bag should never be left in a compression sack unnecessarily and if you over-store it under pressure for too long it can be detrimental to its integrity.

In this article, we will be looking at why a compression sack is a useful tool, how to use them properly, and why you shouldn’t store your sleeping bag in one for too long. By the end of this read, you will know everything there is to know about sleeping bag compression sacks. Enjoy!

Can All Sleeping Bags Be Stored In A Compression Sack

All types of sleeping bags whether natural down or synthetic can be stored in compression sacks for a limited time. The idea of a compression sack is to reduce the sleeping bag’s pack size, so it is easier to transport while hiking or backpacking. Under no circumstances should a sleeping bag be stored long-term in a compression sack.

There are a few differences between natural down-filled sleeping bags and synthetic-filled sleeping bags. Both types rely on the air pockets created within the insulation. These air pockets are what traps warm air to create a barrier between you and the outside cold air, thus keeping you warm inside.

Down-filled sleeping bags use the soft warm under feathers from a duck or goose. When these sleeping bags are stored in a compression sack, they recover quickly when unpacked.

They will quickly regain their puffy insulative qualities (or “loft”) when unpacked from a compression sack. With a quick shake and air out in your tent, a down sleeping bag will be ready to sleep in.

Synthetic-filled sleeping bags are filled with polyester fibers that have been matted together to create an effective insulation.

Synthetic-filled sleeping bags are far more resistant to weather conditions and they can usually be machine washed (unlike down sleeping bags) however they are affected by compression sacks more than their down-filled cousins.

Generally, synthetic sleeping bags need 10 to 15 minutes to air out once they are unpacked from a compression sack.

This means when you set up camp you will have to unroll your sleeping bag in your tent and leave it while you have a cup of coffee, set up the rest of camp, or enjoy your surroundings before using it.

What To Do Before Putting Your Sleeping Bag In A Compression Sack

When storing your sleeping bag at home you should keep it unrolled loosely, hung up in a wardrobe, or placed in a storage sack.

You should always keep your sleeping bag clean and dry and if you have been using it regularly, it should go through a deep clean. How you deep clean your sleeping bag will depend on whether it is natural down-filled or synthetic-filled.

You should follow the manufacturers’ instructions and refrain from putting it in the washing machine unless you know 100% that it will be okay for the sleeping bag.

General maintenance and storage aside, there are a few things you should do before storing your sleeping bag in a compression sack for an upcoming hike or backpacking adventure.

You should pack your sleeping bag in its compression sack just before you head out on your adventure rather than packing it way ahead of time. The longer you stuff any sleeping bag in its stuff sack, the flatter it will become and the longer it will take to regain its loft.

Before you stuff your sleeping bag into its compression sack you should give it a good shake to spread around the insulative filling evenly throughout its length. Once you have shaken it and spread out the filling, flatten it out to get some of the air out. Doing this will help the insulation compress evenly as you roll it up, stuff it, and compress it. As a result, when you unpack the sleeping bag the filling will expand evenly and regain its loft much quicker.

You have two options when it comes to fitting your sleeping bag into its tight-fitting compression sack. These are the roll and the stuff. I prefer to roll up my sleeping bag to stuff it into my compression sack as I find this works better for my setup and seems to be easier for me.

Many people prefer to stuff their sleeping bag into the compression sack. It depends on what you find easier and what works better for your sleeping bag.

To roll your sleeping bag up, roll from the foot end to the head end with the zipper fully shut. This way, the air will push down the bag and escape through the opening at the top allowing you to produce a tighter roll.

Once your sleeping bag is rolled, you can clamp it between your legs and slip the compression sack over it. You will likely have half of the rolled sleeping bag sticking out the top of the sack, with this, start stuffing it down into the compression sack until it can be closed and compressed.

To stuff your sleeping bag into its compression sack, you should start from the foot end and systematically push the sleeping bag fold-by-fold into the bottom of the sack. Once you are at the head, you can stuff the whole lot down as far as possible and pull the drawstring on your sack.

It will take some time until you get good at this, but over time, you will get the knack for it and it will be much quicker than the rolling method.

How Long Can Sleeping Bags Stay Compressed?

As we have mentioned throughout this article, you should never leave your sleeping bag under pressure in a compression sack for any longer than necessary. They are just a means of compact transportation to make bringing your sleeping bag on a hike or backpacking adventure easier.

Although there is no specific “unpack” time on your sleeping bag when it is in a compression sack, there are some guidelines you should stick to. Generally speaking, you should not leave your sleeping bag in a compression sack for longer than 12 hours at a time.

This is only a guideline though, and you shouldn’t worry if your sleeping bag is compressed for longer than this. It is not like it will be ruined if it’s stored for another few hours or even a day like this.

What Happens If Sleeping Bags Stay Compressed For Too Long?

Leaving your sleeping bag stuffed in a compression sack for too long will eventually lead to the degradation of the loft (the puff of the insulation).

This goes for any sleeping bag whether down or synthetic. In the short term, you will find your sleeping bag (no matter the filling) will be a bit flat when unpacked after a period of compression. This is fine and it will puff out again after a quick shake and an undisturbed air-out in the tent.

Packing your sleeping bag too tight in the compression sack can also lead to permanent degradation of the insulation. This is especially true if your sleeping bag is filled with down. The barbs of the tiny down feathers inside your sleeping bag can become bent, split, and damaged which will prevent them from ever producing that lifted airy loft that it once had.

If you are using a down-filled bag, you should make sure not to over compress it. If you are using a synthetic-filled sleeping bag you will get away with compressing it more, but it is important to lessen the time it is compressed in this state to prolong its life.

You can avoid degrading the insulative qualities of your sleeping bag by reducing the amount of time it is left under compression and properly storing it when it is not in use.

Sometimes it can be difficult to stick to leaving your sleeping bag packed for as short a time as possible especially if you are backpacking and traveling a lot. I have had my sleeping bag stuffed for over 2 days at a time when taking international flights and I have had no issues, but I make sure that as soon as I can, the sleeping bag is taken out and aired out.

If you are traveling long distances with your sleeping bag in its compression sack, it is best to leave the compression straps un-tightened. When you can, at airport layovers or in hotel stop-overs get your sleeping bag out and sir it out. Sure, you’ll look a bit strange, but your sleeping bag will be grateful for it!

Overall, your sleeping bag should only be compressed for 12 hours maximum but with the nature of travel, backpacking, and hiking it is not always easy to stick to this.

To be honest, it doesn’t matter too much if you have your bag compressed for a long period of time here and there, just make sure to look after your kit. Keeping your sleeping bag dry, clean, and stored long-term properly is far more important than the amount of time you leave your sleeping bag compressed.