A good sleeping bag can be the difference between a really pleasant camping trip and a miserable, exhausting adventure. Since it’s a somewhat hefty investment, you don’t want to make an uninformed decision. So when buying a sleeping bag, you should try on as many as possible, no matter what store you enter. Get inside and zip ‘em up. Roll around a bit. Wiggle your feet and toes.

To help you make sense of modern sleeping bags, we’ve compiled some info as a starting point to choosing a good bag. We’ve tried to keep it relatively simple.

First things first –

The Anatomy of a Sleeping bag

• Footbox – A roomy contour in the foot area that helps your feet lay in a natural position.
• Baffles – Lateral compartments sewn into the bag to keep insulation evenly distributed.
• Shell – The outer fabric of a bag.
• Draft Tube – Insulated tube running alone the zipper to help insulate this heat leak.
• Liner – The material that sits next to your body.
• Hood – The material that surrounds the head, helping to lock in heat and greatly improving the efficiency of the bag.

 

Key Factors

• When/Where: Determine what time of year and in what kind of temperature you’ll use the bag. What’s its intended use?
• Insulation: You will have a choice between down and synthetic fill.
• Temperature Rating: Get a bag rated to the coldest temperature in which you’ll be camping or sleeping. Do you need 1 bag for all year, or will you be budgeting for multiple bags?
• Weight/Packability: If you’re backpacking a lot, ounces have a huge impact.
• Fit: Have you had problems with comfort of previous bags? What made you uncomfortable?
• Women Specific: Designed with more insulation in spots where women lose more heat then men; They are also shorter in length and tighter in the shoulders to reduce air pockets.

 

When/Where

Before you start looking, it’s good to know your camping habits and desires. It’s important to know when you’ll be using the bag and in what kind of conditions. Keep the following in mind while you shop or do research:

• What kind of camping are you going to be doing? Car, backcountry, trailhead, backpacking? Where will you be most of the time?
• In drier or damper environments? Will you be in extreme heat or cold?
• Are you someone who cranks the electric blanket to 10 AND uses a down comforter? Or do you naturally emit heat like a space heater? Or: are you a “cold” sleeper or a “hot” sleeper?

 

Insulation

Down is generally better than synthetic insulation. Down is lighter, more compressible, and has a higher warmth-to-weight ratio. It comes in a variety of weights so you can be more selective when you finally decide what kind of bag you need. It generally lasts longer with proper care. And when you’re nestled inside the bag, it seems to float over you and feel light and airy.

Synthetic insulation is great when you’re going to be in moist or damp environments a lot. Perhaps you spend your time camping near rivers (are you an overnight raft guide?), in the Pacific Northwest, or in the woods of Maine in summer. Synthetic insulation keeps its insulating properties, even when wet. It also dries much more rapidly if it does get wet. The slightly heavier, bulkier synthetic bag isn’t a bad idea when you know water’s a factor. Most of the synthetic bags we carry at The Alpineer have Polarguard® Delta, Polarguard 3D, PrimaLoft, or a propietary synthetic fill.
 

Shells & Linings

The exterior of new bags feels so light and fragile you wonder how it can keep the elements out much less keep the insulation in. The secret is tightly-woven nylon (Ripstop or Taffeta) or polyester (usually Taffeta). Taffeta and Ripstop are made of a hatched, super-smooth, silky fibers. They’re in a fine, tight weave that adds strength, making it highly abrasion-resistant and also (as the name suggests) don’t readily rip end-to-end when a break does form.They’re designed to breathe, just like a down or synthetic jacket. And they’re durable.

In a very broad sense, polyester tends to be softer on the skin, but you probably wouldn’t be able to tell the difference if you bought a bag with a nylon interior. Polyester also has a higher resistance to UV degradation but has less stretch to it compared to Nylon, making it slightly more prone to tearing.

Other features to look for in the fabric are items such as water resistance. Mountain Hardwear brought out bags with all-welded seams in 2006, eliminating stitching which improves insulation and water resistance. Also look for Gore-tex for a breathable, yet highly waterproof bag.
 

Temperature Rating

A temperature rating, also called comfort rating, is given to each bag to tell you the how cold you can go. It’s generally based on a US standard test, ASTM F1720, that puts a heated dummy into the bag and tracks temperature readings and a variety of temperatures. Unfortunately, the standard has notorious inconsistencies from lab to lab.

But temperature rating is still a nice guideline to help you figure out which bag to get. We carry a lot of bags rated 15-20º because this is a great range that can handle three seasons in most environments. We advise that you trust the rating based on your own metabolism and sleep habits.
 

Weight & Packability

If you’re car-camping, you don’t mind if a bag’s on the heavy side (we’re still talking less than 4lb, though). Sometimes that means you can have a bit more insulation if that’s what you want. But if you’ll be strapping a bag onto your pack, weight and packability play as much of a factor as insulation. You want to find a balance so that you’re not sacrificing comfort or convenience.

Generally, a higher rated bag is going to be lighter than a lower rated bag because the higher rated bag doesn’t require as much filling to keep you warm.

A safe 3-season bag is often rated 15-20º to handle potentially chilly nights in places like Crested Butte or Moab where the temperature can drop much lower and then the day is warm.
 

Fit

The fit of a bag is key. Make sure to get in a lot of bags to see what you like and don’t like. Buying a sleeping bag is a major investment and to have one that you just don’t feel right in is extremely frustrating.

Air gaps in a bag that is too big are also a problem because they make a bag generally colder. Your body has to heat that additional air up too in order to stay warm. They additionally add a convective element, increasing the rate at which heat is leaving your body. Bags with draw chords or elastic are a great way to reduce gaps. As a bonus, they also keep the bag with you as you toss and turn in the night.
 

Women Specific

Most manufacturers understand that women and men sleep differently. Men generally sleep warmer than women, and women generally lose more heat than men. Women-specific bags these days account for these differences by putting more loft in certain spots like the footbox and the upper torso. Although they’re relatively narrower and shorter, they have a bit more girth in the hips. Even if the difference is only 2-3″, that can impact a woman who’s only 5′2″.
 

Other Factors

Sleeping bags have come so far in recent years. It’s almost like bringing the comforts of your own bed out on the trail. They seem to have everything except the space of your king-sized bed. (Although, if you’re a roller, you could have the whole forest floor on which to move.) Among the array of extras you can get, some that rank high on our list are 2-way zippers for ventilation at the feet, draft collars, face muffs, and/or head gasket to keep warmth in the bag, draft tubes down the zipper, and locking zippers.

Other features like pillow pockets, stash pockets, and price can also factor into your decision. Rank them on your wish-list as you desire.

Almost any bag from a performance brand, except for the warm-weather bags (generally rated at 35° and higher), have some sort of face muff or head gasket to keep your head nestled which can be cinched closer to your face to keep drafts out. Some have an internal draft collar above your shoulders for further warmth. And almost all perforamnce bags have a comfort or contoured footbox that lets your feet lay in a natural position without the bag squishing down on your feet.

Unique to Big Agnes is an integrated sleeping pad ‘envelope’ into which you slip your pad so you don’t roll off of it in the middle of the night. They can accomodate any manufacturer’s pad so long as you have the properly sized and shaped pad to match your bag. And since the insulation and thermal regulating powers of your pad should keep you warm or temperate beneath you, Big Agnes removes the insulation from the bottom of your bag and either eliminates it to reduce to the weight, or redistributes it to give you more insulation throughout.

The list of features can go on. The key is to take a look at the features in the bags you’re looking at, and determine their importance to your camping life.
 

Finally Deciding

We think the first thing you should decide is which kind of insulation you want. From there, the weight might be the second-most important factor. At some point, price might help make your decision, and some manufacturers are certainly less expensive than others but are no less worth their weight (or lack thereof!) in quality.

Also make a visual inspection for warmth. Look at foot box, hood, and draft tube. Are there any obvious leaks or weak spots?

Give the baffles a check too. Are they nice and firm feeling? This indicates that the down is less likely to shift over time and will keep a nice uniform insulation.

Finally, it’s never a bad idea to talk to your friends and find out what kind of bag they have. Direct recommendations are top-notch and let you ask them about the factors that most concern you.
 

Glossary of terms:

• Compressibility – The capability of a bag to stuff down – some premium/ultralight bags: as small as a loaf of bread.
• Down Fill – typically goose feathers. It has a higher insulation-to-weight ratio than synthetic when dry.
• Drawcords – internal strings that can be tightened to keep cold air out of the hood and collar (or loosened to let warm air out, giving a level of adaptability to a bag.
• Foot Vents – Vents designed into the footbox of some bags to allow for controlled heat loss.
• Hook and Loop Tab – A piece of material that secures the zipper to prevent unintentional openings.
• Hybrid – (1) combination of mummy and semi-rectangular bag or (2) synthetic-down fill mixture
• Internal Chest pocket – a convenient pocket for glasses, headlamp, mp3 player or any other night-time necessities.
• Loft – A fill-power rating or a rating number that indicates how much space an ounce of down fills; the higher the fill power, the warmer the bag (per volume of down).
• Over-Bag – A thin bag that fits around a sleeping bag to increase the insulation for colder temps or wet conditions.
• Pillow Pocket – special bag that can be filled to form a pillow or insert an inflatable pillow.
• Stretch of Flex Bags – Elastic sewn between the baffles, passively helping to keep the bag close to the body and making it move with you throughout the night.
• Synthetic Insulation – Heavier and bulkier than down, but keeps its loft better and retains warmth when wet.
• Temperature Rating – There is no universal standard for bag rating (each country has its own standard).
• Two-Way Locking Zipper – Allows bag to be opened from top or bottom and locks in place when not in use.
• Women’s-Specific – Bags with broader hips, narrower shoulders, and slightly warmer design.

Lets hear about your favorite bags or any sage wisdom you may have in the comments!