How to Choose a Sleeping Bag
The type of sleeping bag you'll need depends on the type of outdoors situation you'll be in and how you'll be getting there. Factors include: temperature rating, fill power, weight, water resistance and fill material. Below is a breakdown of each factor. For a list of gear we've tested and can recommend, check out our gear page.
Temperature rating: What is the coldest it's going to be where you're going (think nighttime, worst case weather scenario)? Then lower that temperature by another 10 degrees and that's the temperature rating of the bag you'll want to have. Generally, a 0 degree bag would be sufficient for winter and a 40 degree bag would be sufficient for summer.
Fill power: This relates only to down bags (filled w/feathers). The higher the number, the better. The higher the number, the bigger the feathers are. Bigger feathers means it takes less feathers to keep you warm and less feathers means lower weight and compact-ability. If you're backpacking this can make a huge difference - you'll always want items to be lighter (less weight to carry) and smaller (so you have more space in your bag). If you're just car camping, not an issue - but if you plan to backpack sometime in the future, you might as well invest in a bag with a higher fill power. 850+ is an excellent fill power.
Water resistance: Will you be sleeping outside? Will it be wet where you're going? Is there a chance of condensation in your tent (likely if your tent has no vents, camping in inclement weather or have your tent packed full of people)? Staying warm can be a life or death situation and if you're in the middle of nowhere and you're not dry and warm, you're taking a huge risk. With that in mind, it's always good to get a bag that has some water resistant material. Pertex waterproof is an example of a quality material for a bag. Another thing to consider here is that some manufacturers use down feathers that are treated to be water resistant. That is, even if the feathers get wet, they'll still keep you warm.
Fill material: Down feathers or Synthetic material? Really simple, buy synthetic if you'll only be car camping (where you don't carry all of your gear out into the wilderness and setup your tent right next to your car); buy down for backpacking and in all situations where you'd like to save weight and space. Synthetic material will never be as compact as down feathers (means less space for other gear) and will never be as light as down feathers (means more weight to carry).