Emergency Blanket vs Bivy – 6 Factors to Consider

Emergency blankets and bivvys serve similar purposes, so deciding which one to use can be tough. 

Both emergency blankets and bivvys reflect your body heat and are water-resistant. However, a bivy isn’t suitable for someone who dislikes being constrained, and an emergency blanket is better if you’re on a budget.

To help you further, I’ve done research to put together a more detailed guide below.

Feature	Emergency Blanket	Bivy
Weight	Extremely light	Light
Comfort	Good; best for people who prefer being unconstrained	Good if you don’t mind enclosed spaces
Warmth	Reflects 90% of body heat	Very warm
Versatility	Can be used in many situations	Not versatile
Packed Size	Smaller than your hand	A little bigger than your hand
Price	Usually inexpensive; will have to be repurchased eventually	Can be highly affordable or very expensive

Emergency Blanket Pros and Cons

Emergency blankets don’t immediately spring to mind when thinking about camping gear, but they can be highly beneficial.

Pros

• Budget-friendly; low cost and can be bought in bulk
• Extremely light
• Can be used in all weather conditions

Cons

• No head cover; your face and head may end up cold
• Won’t protect your back
• Difficult to clean; you’ll have to replace them when they get dirty

Bivy Pros and Cons

Bivys come in two forms: sack or shelter. The sack is similar to a sleeping bag, and the shelter has some structure over your torso, making it more like a tiny tent.

Pros

• Can be used instead of a tent
• Reusable can be reused indefinitely where an emergency blanket has a shorter lifespan
• Warm enough to provide comfort

Cons

• Can feel claustrophobic
• Your breath can cause condensation buildup

Emergency Blanket vs Bivy Weight

Winner: Emergency blanket

A single emergency blanket usually weighs less than a pound.

In fact, you can get several emergency blankets that weigh under a pound in total: look at the Oceas Outdoor Mylar Emergency Blanket 4 pack. The shipping weight of the four emergency blankets and their case is under a pound.

A bivy sack by comparison weighs only 4.8 ounces, but one bivy sack is still heavier than one emergency blanket.

Emergency Blanket vs Bivy Comfort

Winner: Varies

You need a sleeping pad with both pieces of gear, so the comfort level there is about the same. As neither has padding, the comfort factor is solely dependent on whether you’re comfortable in cramped spaces or not.

If you enjoy being tightly wrapped up, then you’ll prefer a bivy bag. If you want more wiggle room, then an emergency blanket will likely appeal to you most.

Emergency Blanket vs Bivy Warmth

Winner: Emergency blanket

Emergency blankets reflect 90% of your body heat, so they’re always going to be at least a little warmer than a bivy.

Some bivvys also reflect this much body heat, but not all of them do, so it’s difficult to generalize. 

Both items will keep you plenty warm when you need them to, though, so you’re not losing out on anything regardless of which one you pick.

Emergency Blanket vs Bivy Versatility

Winner: Emergency blanket

Neither an emergency blanket nor a bivy are too versatile, but a bivy sack is less versatile than an emergency blanket.

You can only use a bivy one way: crawl into it, close it up, and stay warm. However, emergency blankets are essentially big sheets of fabric. You can use them in plenty of ways.

You can suspend an emergency blanket like a tarp for some shelter above you. You can wrap an emergency blanket around you like a cape and walk with it on a cold day. You can even sit on top of an emergency blanket if the ground is too cold to sit on.

Emergency Blanket vs Bivy Packed Size

Winner: Emergency blanket

Both of these items roll up incredibly small, but the emergency blanket has to win. If we look at the Oceas blanket from earlier, a single emergency blanket rolls up smaller than your palm, and four of them in a holder are smaller than a single packed bivy.

That said, bivvys are still quite small. They’re often not much bigger than your hand when rolled up tightly and packed away.

Emergency Blanket vs Bivy Price

Winner: Varies

Pricing can vary a ton between emergency blankets and bivy. Emergency blankets seem more affordable at first glance, as you can get four for just over $20, and in some cases, you can get 10 for just over $10! 

But you have to remember you’ll have to rebuy them at some point.

Bivy sacks vary in price, too. There are some great ones available for under $30, but they’re usually the ones made for emergency use. Studier, longer-lasting bivy bags can cost over $100 as you can see with this Snugpack Special Forces bag.

Alternatives to Emergency Blankets and Bivvys

Sometimes neither of the options described above will make you comfortable, but there are alternatives that you might wish to use instead. 

Wool Blanket

A wool blanket won’t keep you as warm as an emergency blanket, but it’s always a good option if you like being cozy. I don’t recommend using one when it’s extremely cold outside, but it’s a good option for early fall and late spring trips.

You can layer wool blankets for extra warmth, but keep in mind that they’re very heavy and expensive, so they’re best for car camping.

If you want to see how a wool blanket compares to a sleeping bag, then I suggest you read up on the details of using a wool blanket vs sleeping bag.

Mummy Sleeping Bag

A mummy sleeping bag is the closest thing you’ll get to a bivy without it being a bivy. Mummy sleeping bags are highly insulated and wrap you up tightly. There’s even a hood, but your face will be exposed so you won’t feel quite as constrained as you would in a bivy.

Three are other types of sleeping bags, too, but a mummy bag will keep you warmest. However, you can still take a look at this mummy vs rectangular sleeping bags comparison if you want to choose the best sleeping bag for you.

Single-Person Ultralight Backpacking Tent

If you want something roomy that’s not quite as large as a tent, then consider something like this. It’s a single-person tent that’s just a little bigger than a bivy shelter, but it’s not quite a full tent.

They’re narrow, but there’s lots of headroom for you to sit up by day or night.

Camping Quilt

A camping quilt is like a mummy sleeping bag without a back. It fits to your body, tucking you in, but your back and head are free so you won’t feel as constrained. 

These are great for people who don’t mind their legs being wrapped up tightly, but who have issues with claustrophobia when their head is obscured.

Is There A Winner?

There’s no way to say whether an emergency blanket or a bivy is best, as they’re highly similar. It’s up to what you feel is a better fit for you.

I recommend investing in both and trying them out in different situations, as you never know which one you’re going to click with.