Sleeping bag

Is this generally an essential? Yes

Sleeping outside (even in a tent) is very different than sleeping indoors: you're more exposed to the outside temperatures & winds. Therefore you want something that wraps more snugly around you to effectively trap body heat & keep you warm - this is a sleeping bag! As you'll read on later, along with sleeping bags, sleeping pads are also part of your outdoor warmth system!

We carry for rent & sale: Sleeping bags rated from 0 to 30 degrees Farenheit (-18 to 0 degrees Celsius), in standard 6 foot (1.8 m) lengths with standard girths

  • For rent only: extra-wide, extra-long, short, & women's specific bags


Choosing your gear


The key material in question is the filler material (the insulation), which keeps you warm. In short, the more a space a filler material occupies (i.e., the more it "lofts), the better body heat is trapped. This is why you see "puffy" jackets.

By this logic, it follows that when you use a sleeping bag, the underside of you, where your body weight compresses the bag, actually doesn't insulate that well! That's why a sleeping pad is really important, to prevent heat loss from your underside to the ground.

Filler material can be found naturally in down (the fluffy part just at the root of the feather from ducks or geese), though this is more expensive. Filler material can also be produced synthetically; there are various proprietary synthetic-only or synthetic-down blends used in the market. We'll quickly discuss the benefit of each type of material:

  • Down: Natural down is unbeatable in terms of weight-to-performance, i.e., the same weight in down will keep you much warmer than the same weight in synthetic. Down lofts better, meaning that can compress down more, and pack down super small. By the way, down is described by its fill power; the higher the fill power, the more loft is achieved (the more it fills space) & the better the weight-to-performance ratio
  • Synthetic: Made to perform even in sub-optimal conditions (e.g., retains heat even if not fully lofted & even if wet, although soaking wet is a very different matter!). As a man-made material, it is cheaper than than natural down & the only option for those with down allergies or those who are strict vegans who stive to remove all animal products from their lifestyles
  • Synthetic-down blends: Manufacturers blend both in various ways to try to get the best of both worlds. How this compares to down or synethetic alone depends on the exact blend in your brand/model

Note, manufacturers continue to address one of down's biggest weaknesses: that when it gets wet it stops lofting as well & therefore its insulating ability weakens. Down bags have their shells treated with water repellancy & the down itself can be treated to be more hydrophobic, or water resistant. That said, down is still more susceptible to weather than synthetic & this should be an important consideration for your trip.

Temperature rating

This refers to the optimal temperature the manufacturer designed the bag to be used with. For example, a 0-degree bag is designed for a colder environment & is thicker; a 30-degree bag is designed for warmer weather & is thinner.

When looking at a sleeping bag’s temperature, you may see a spectrum. This is the European Union's attempt to universalize temperature ratings across manufacturers & models. The EN comfort rating is the lowest temperature at which a bag will keep the average cold-sleeper comfortable with a base layer & a sleeping pad; the EN lower limit rating is the lowest temperature at which a bag will keep the average warm-sleeper comfortable with a base layer & a sleeping pad.

Generally, women tend to be cold-sleepers & men tend to be warm-sleepers, so women may find the EN comfort rating more useful whereas men may find the EN lower limit more suitable. For more info on women-specific sleeping bags, click here.

All that said, sleep temperature is very personal! You should find out what works for you (renting is a great way to test various ratings). We generally recommend getting a sleeping bag with a lower temperature rating than the actual night time temperature forecasted. This is because sleeping outdoors exposes you to the elements in a way that sleeping indoors does not. Some ways to adjust temperature:

  • To add warmth: wear more layers or use a sleeping bag liner. The goal is to create more filler material to trap body heat. For more tips, see our protip on winter camping. Keep in mind, there's a limit to how many layers you can add before the sleeping bag fits too tight
  • To remove warmth: remove layers or unzip the sleeping bag. NOTE: if you unzip a bag, the part that's unzipped can be really cold while the part that's inside can be really hot! Using a sleeping bag liner or wearing layers will help regulate, but it's more art than science


Speaking of temperature, sleeping bags, unlike regular blankets, seek to trap as much body heat as possible using not only the type & quantity of material, but also the shape!

  • Mummy bag: They're named mummy bags because they are narrowly cut to fit snugly around the contours of your body. This shape minimizes drafts & dead space inside the bag. Completing the mummy effect, these bags have a hood, which can be cinched tightly such that only your nose & mouth pops out for breathing!
  • Rectangular bag: This is basically a regular blanket folded in half & in-fact, often can unzip to become a regular blanket. So how does the shape help keep you warm? Well... compared to a mummy bag, it doesn't! But compared to a regular blanket, the fact that it can zip all the way around you is still more helpful than if it didn't. Depending on your size needs given girth or sleeping preference, these may create a snug fit needed for efficient trapping of body heat

Performance-aside, some people simply do not like to sleep in a snug environment, in which case it's important to make sure you can stay warm without a fitted sleeping bag.

Size & Weight

  • Material: As described above, down has a high weight-to-performance ratio. Backpackers prefer down bags for its lightweight & super compact qualities
  • Temperature rating: As described above, bags rated for lower temperatures have more filler material, so tend to be thicker. Given this, if you need a thick, low-temperature bag that's also lightweight, generally you're limited to down bags
  • Style: As described above, a rectangular bag is larger than a mummy since it's less form-fit & there's more material. Read on below to find out more about how girth & sleeping preference may also play a role in the style of bag
  • Length: A sleeping bag should be about your height or a bit taller. Adult bags come in 5.5 feet to 6.5 feet (1.7 to 2 m)
    • Too short and you may not be able to get entirely inside of it (that said generally, most bags have a slight buffer; a bag that 5 feet 6 inches will fit someone who's 5 feet 8 inches)
    • Too long and there will be more dead space
  • Girth: Because sleeping bags are designed to wrap around you snugly, girth is also important. That said, the standard sleeping bag is designed to fit the average person, so most people will not need to consider this dimension on sizing. For those who need extra consideration, here are some quick guidelines (we carry the below types of bags for rent as well)
    • Extra-wide: Many models have an extra-wide option (keep in mind, extra wide options are almost always also extra-long, likely a 6.5 foot [2 m] bag, which may create dead space if you're not that tall)
    • Rectangular: If an extra-wide sleeping bag still feels tight, you can use a rectangular sleeping bag that can unzip into a regular blanket, which may also be better depending on your sleeping preference

    Note, sometimes you can find a more-narrow-than-standard girth bag, which is preferred by backpackers for even more weight savings.

Sleeping with others

  • Sleeping with an adult partner: Sleeping with a partner creates dead space & so may not be the best idea. It can also be hard because you & your partner may run different temperatures (one may be a warm-sleeper and the other a cold-sleeper) & zipping or unzipping the sleeping bag can affect you both. If you're interested, consider the following options:
    • Using a double mummy bag. Probably the best option, it's designed to conform around 2 bodies
    • Zipping 2 mummy bags together. This option is less effective than a double sleeping bag, because you'll have 2 foot boxes & 2 hoods (the bags connect along the zipper line), which can be awkward to manage when sleeping together
    • Using a rectangular sleeping bag fully un-zipped or a blanket. This is just like sleeping together at home! Again though, this may only be possible in warmer temperatures
  • Sleeping with a baby or child: In most cases, you'll need an extra-wide or rectangular bag to accommodate

Alternatives you can use

  • Regular blankets: as a rule-of-thumb, if you find yourself looking for a 50-degree Farenheit (10-degree Celsius) sleeping bag, it's entirely possible that a regular blanket will suffice. Keep in mind, though, that the shape of a sleeping bag also matters in keeping you warm
  • Backpacking quilts: not the same as a normal quilt, these are basically a sleeping bag missing its underside. Quilts derive from the logic that, if the underside of the sleeping bag isn't very insulating, just remove it to save weight! As a result, it becomes even more important to have a sleeping pad to maintain warmth. Finally because a quilt doesn't fully fit around you, it can feel drafty in windy conditions.
  • Hammocks: can potentially substitute for your tent, sleeping bag, and/or sleeping pad all-at-once. That said, most people choose to add a sleeping bag or quilt & a pad for additional comfort & warmth. Be sure there are plenty of trees & you're comfortable sleeping without support for long periods of time (it can result in back pain for some & back pain relief for others). Modern hammocks can also come with insulation or a top covering to protect from rain & bugs

Using your gear

The issue with dead space & how to fill it

We've discussed a number of ways dead space can arise in a sleeping bag due to it not fitting snugly around you, e.g., you sleep with a partner, your bag is too tall for you or too wide for you, etc.

Dead space is a problem because your body wastes energy heating it up, which reduces the efficiency of the sleeping bag in keeping you warm. To minimize this, fill the space with whatever available, e.g., extra layers (back in the day, people stuffed wadded up newspapers in their jackets as a warming-hack!), something else that also generates heat like a sealed hot water bottle. If it's a sleeping bag, you can also try to fold the excess length underneath you.

How to stuff it in its stuff sack

Don't roll, just stuff (starting from the foot box so that air is squeezed out as you go)! Sleeping bags are designed to be compressed so stuffing doesn't damage anything & it's far easier than a neat roll. To get a sleeping bag even more small when packed, use a compression sack, which has straps on each side you can pull down on to tighten.

Use the stuff sack!

Classic campers will stuff the empty stuff sack with clothes & use it as a pillow. In fact, some stuff sacks even come with a soft velvet side designed for this use! For this reason, we don't offer separate camp pillows.

Keeping dry

Although the outer shell of a sleeping bag is often treated to be water-resistant, it's always important to keep a bag dry, since, depending on its material, its performance may be completely impacted by becoming wet. In addition to keeping the sleeping bag inside a waterproofed backpack or tent at all times, you can also think about stuffing it into a trash compactor bag & then into your stuff sack, or using a waterproof stuff sack.

How to zip 2 bags together

Firstly, zippers must be on opposite sides. Zippers also should be the same length to create the best fit, which generally happens with 2 bags of the same brand/model.

Cleaning, repairing, & storage

Store loose or hung

Some of the newer trends include a single sleep system (since both bags & sleeping pads are essential for warmth & comfort). Now you see combination sleeping bags & pads, or sleeping bags with slots designed to fit a sleeping pad. Even pillows are making it into the integration; some sleeping bags have pockets for pillows! These integrated systems are great, but may not offer the flexibility that some people require (e.g., customizing based on colder temperatures, or backpacking and weight-conscious situations).

Thoughts, ideas, questions? Let us know in the comments below! We're Last Minute Gear, and we'll do our best to get you ouside!

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