How Long Does A Synthetic Sleeping Bag Last?

When looking to decide what sleeping bag is right for you, you’ll want to consider different materials and the benefits and drawbacks of each. One of those factors is how long the sleeping bag lasts before needing to be replaced.

A synthetic sleeping bag lasts for 7 years on average, meanwhile, a down sleeping bag lasts for 10. However, this amount of time can increase or decrease depending on the number of times you use it in a year and the way in which the sleeping bag is stored when not in use.

As much as there are many different points that will affect that timeline overall, four years is a good rule of thumb. Of course, if your synthetic bag is damaged then that will affect its lifespan. Taking good care of a synthetic sleeping bag, repairing it, and cleaning it regularly, is the best way to ensure that it will last for a longer time.

Why Do Synthetic Sleeping Bags Need To Be Replaced?

There are obvious reasons why you might want to replace a synthetic sleeping bag, but there are also less obvious ones. On the less obvious end of the scale, it’s likely that you may have sat on or lain down in your sleeping bag and discovered that there’s something wrong, without having the word to describe exactly what it is.

In that case, it’s likely that the sleeping bag has lost its loft. This is when the fibers which make up the filling of a sleeping bag begin to line up in suboptimal ways and start to collapse. While collapse might be a dramatic word, it’s also a great way to describe what’s happening here.

Imagine you’ve got a handful of chopsticks. You throw them on a counter, and they fall in a multitude of ways, some stacking up to form little pyramids, and others lying flat.

Through continued agitation of the pile, more and more chopsticks will fall, until they’re all lying flat on the counter. This is the same thing that’s happening in sleeping bags, though with tiny synthetic fibers instead of chopsticks, and therefore on a much smaller scale.

Of course, there is a difference between more expensive synthetic sleeping bags and cheaper ones. In high-quality synthetic sleeping bags, the filling is likely to contain fibers that are much finer than cheap synthetics.

The upside of this is that it gives the bags greater insulation, plus they’re often much softer and forgiving. The downside, however, is that they may need to be replaced sooner. The fine fibers within high-quality synthetic sleeping bags tend to lose their loft more quickly than the rougher, thicker fibers of their cheaper counterparts.

The difference in the fibers of a sleeping bag means that they will be more or less supportive, of course, but it also means that they’ll insulate you to different degrees.

Generally speaking, cheaper sleeping bags will insulate you worse than a more expensive sleeping bag would. In simple terms: an expensive sleeping bag will keep you warmer for longer than a cheap sleeping bag would.

In terms of longevity, the heat retention of a sleeping bag lasts for roughly the same amount of time as the thickness of it does. As with when you’re wearing many layers of clothes, it’s the air that you trap which leads to good or poor insulation.

Going back to our chopstick analogy: when the fibers are stacked up like a pyramid, they can trap more air. This air means that they can insulate you better. Therefore, as the fibers fall, the sleeping bag gets worse at retaining heat at the same rate that it loses its fluffiness.

How To Make A Synthetic Sleeping Bag Last Longer

There are a huge number of ways to make a sleeping bag last longer, so let’s go through some of the ones we think are most important. There are bound to be some that we’ve missed, but we think these ones are particularly good to bear in mind.

Keep You Sleeping Bag Dry

No matter the filling of your sleeping bag, the fibers of the bag are likely to store and retain fluid if they get wet at all.

The army used to used organic feather and down sleeping bags, for example, but the reason they stopped is that after getting rained on the bags would become waterlogged and incredibly heavy.

In order to dry out your sleeping bag as well as you can, make sure to remove the bag from its compression sack, and store it somewhere dry, loose, and cool. A great place could be in a closet, or under a bed, wrapped in a sheet.

In our modern world, the vast majority of us have tumble dryers or, at least, clothes horses in our homes.

While you can definitely throw a damp sleeping bag on a radiator or over a clotheshorse to dry out, it may be worth checking the label to see if you can throw it in the tumble dryer. If so, then make sure to keep it away from any cats: a warm, cozy spot like that is sure to entice any that may be nearby.

Minimise The Number Of Times You Wash Your Sleeping Bag

The fibers in a synthetic sleeping bag are designed to capture and trap air so that they can insulate you.

They’ll do just that, but they’re also likely to capture and trap water from being washed. This means that if you wash synthetic sleeping bags too much, you’re likely to needlessly agitate the fibers, causing pre-emptive degradation of the quality of the bag.

In order to make sure your sleeping bag’s properly clean at all times, you should treat it as though it’s a synthetic jacket, and wash it only when it’s dirty.

As a good rule of thumb for washing your sleeping bag, you should make sure to wash it when you can notice that it smells bad. Of course, that may be a natural time to wash it anyway.

If you’re unsure of when to wash your synthetic sleeping bag: synthetic bags are likely to pick up oils from your body, which will get embedded into the fibers. When that happens, the bag will lose loft and warmth, which is definitely something that you’ll feel.

Keep Your Sleeping Bag Away From Open Flames

Synthetic sleeping bags and jackets can be particularly susceptible to sparks and open flames. As much as you might have been told that a sleeping bag should really stay in the tent, there’s every chance that you’ve scooped it up to sit next to the campfire. I can’t blame you, I still do that now!

However, even if you believe that you’ve made a particularly compact and contained fire, the nature of fire means that you can’t be too sure.

One of my sleeping bags has a little cluster of stings near the feet where I was sat just too close to a fire and sparks had decided that I was their enemy. Suffice to say, a burn mark, no matter how small, can spell the beginning of the end for a sleeping bag, synthetic or not.

The synthetic fibers in a sleeping bag are spectacularly good at catching fire. This is because, like all highly flammable materials, they’re great at catching and trapping air.

This high air-density means that there’s plenty of oxygen for the fire to feed off, so as soon as you catch alight, things will go south very quickly.

As I said at the beginning of this section, make sure to leave your synthetic sleeping bag in the tent so that it, and you, don’t catch on fire.