What Makes A Winter Coat Warm?

What makes a winter coat warm? So glad you asked.  With so many winter coats to choose from, it can be nearly impossible to decipher the warmest coast for you! The outdoor gear lingo can be confusing too:   DWR, breathable, waterproof, wind resistant, insulated, soft shell, hard shell, fleece hybrid….. what does it all mean and how will it keep me warm? Don’t get too overwhelmed.  I’ve already done all the grunt work for you- to help you choose the right winter coat for your activity.

What’s the Coat for?

Layering To Stay WarmBefore you even begin shopping for a warm winter coat you need to ask yourself what you will doing in the coat? Will you be scaling the jagged edges of Denali or do you need a nice warm coat to walk your dog in Central Park? The same go-to coat for skiing may not work for your ice climbing adventure set for later this month! Once you narrow down what you need the coat for, you can choose the right coat to keep you warm.

If you’re going to be really active and prone to sweating, you’re going to need a coat that is breathable and just enough insulation to keep you warm, but not too warm.  However, if you are going to be ice fishing all day and you’ll be sitting in one spot for hours on end, waiting for something, anything to bite, you may gravitate toward a down coat that works wonders at keeping you warm.

Layers of a Coat

Canada Goose-Perley 3-In-1 ParkaThere are several elements to a winter coat that give it warmth.  Let’s take a look at those layers, so you know what to look for the next time you’re in the market for a new winter coat. The insulation keeps your body heat where it belongs, next to you and the outer shell of a coat keep the wind and wet weather from penetrating and seeping into your other layers.  The sole purpose of a coat is to keep you warm and keep you dry.

In fact, if you stay dry you are guaranteed to be warm.  Water has an incredible way of drawing heat away from your body.  If your coat gets soaked, your body temperature will start to drop, you’ll start to shiver and enter the beginning stages of hypothermia.  Don’t go there! It’s easier to stay warm, then it is to get warm- especially outside in subzero temperatures.  A well-insulated and water-proof/wind proof coat will keep you warm and prevent hypothermia from setting in!


Insulation is one reason why you love that Patagonia down coat for extra cold days.  There are basically two main kinds of insulation used to make winter coats warm: down and synthetic fill.  I’m always down with down.  Down is lightweight and it has incredible insulating properties.  The higher the fill count, the warmer the coat.

Some outdoor experts recommend staying between 650 and 800 fill for a down coat.  Many people believe down is made out feathers, it’s not! In fact, down insulation is made out of a soft layer underneath the feathers of a goose or duck.  This soft, insulating powerhouse material is called plumage! There, now you can wow your hiking partners with some outdoor gear trivia.  You’ll get serious trail cred!

Down is perfect for cold and DRY conditions.  However, the moment it starts to snow, that down coat loses its insulation power.  Down does not hold up well in wet weather! So, if you are planning on skiing or hiking in conditions where it could snow, rain or hail, you may want to throw another waterproof shell over your down coat or choose another coat for that adventure.

Because down coats are so light weight and fold up really easily, I always like to keep an extra down coat in my pack or car just in case I need another layer to warm up.  If you’re winter camping, there’s nothing like pulling out a down coat to warm up around the fire.  If it’s really cold, down is comfortable enough to sleep in.  One thing to consider, down can be expensive.  I think it’s a good idea to always have at least one down coat in your gear pack for cold days.

Synthetic insulation is bit bulkier than down, but it will keep you warm no matter what Mother Nature has in store for you! Synthetic insulation is made with polyester fibers, designed to trap in warmth, even when it’s snowing buckets outside. This insulation also dries a lot faster than down, if you ever find yourself trapped in a blizzard without any where to seek shelter.  Synthetic is also hypoallergenic, which is a good thing if you are sensitive to down plumage.  Synthetic material is also a but more budget friendly on the old wallet.

If you need a coat that can withstand a variety of conditions, a synthetic insulated coat may be the best bet for you.  With a synthetic filled coat, you will stay warm on rainy days in the mountains, picking the kids up from school on an oh-my-gosh- it’s-snowing-cancel-school-day and on a bluebird day on the ski slopes.  A synthetic filled coat is more versatile than down coat.  However, if you can afford it, it might be nice to have both! I never head to late fall football game without a down coat!

Both synthetic and down are excellent at keeping you warm.  The main goal of the insulation is to keep body heat, close to your body!  Keep in mind, the technology for winter coats is changing so quickly, you may encounter a variety of inner liner and other materials designed to help you generate body heat.

Columbia Sportswear recently releases a new line of jackets with Omini-Heat reflective material.  According to the company, an Omni-Heat coat is lined with silver dots, designed to reflective body heat and give it back to you.  What a polite jacket! The material is also breathable, which prevents you from getting too warm! Other companies have variations of this technology and all of it is designed to keep you warm.

Outer Shell

Fortress Jacket Outer ShellThe outer shell of a coat is designed to keep weather away from your body.  It’s protection from the 25 mile an hour winds at the top of Mount Rainier or the fierce Nor Easter that blows in every January off the Atlantic.  Think of the outer shell as body armor against the unforgiving winter weather conditions you may encounter.  Back to the outdoor gear lingo. Stay with me.  There are a variety of shells: soft, hard and a hybrid.  A soft shell is well, soft, and moves with your body.

I know, call me captain obvious from now on.  A hard shell doesn’t move with your body and tends to be fairly rigid.  In some activities and weather conditions, a hard shell may be necessary.  A hard shell is great for mountain climbing where you will encounter fierce weather or skiing where you wind will be whizzing by you as you master that run with all the moguls.

A hybrid shell is half soft, half hard shell- giving you the best of both worlds.  The kind of shell you choose really comes down to personal preference.  In general, if all shells are waterproof, windproof or water-resistant you are going to stay warm.

Waterproof and Water-Resistant

Fortress Bug Out BagA winter coat that is waterproof or water-resistant will keep you warmer than a jacket not designed to repel water.  Remember the key to staying warm during the winter months, is staying dry!  Please note, waterproof is not the same as water-resistant.  A waterproof coat will repel water and keeps it from seeping into your coat, through your layers and into your body!

Waterproof coats are designed to withstand extreme wet weather.  Water resistant will keep you dry, but only for so long.  A water-resistant coat is great for a light drizzle, like walking through Pikes Place Market in Seattle in September.

However, if you try wearing that same coat in December during a torrential down pour, you’ll be soaked to your bones and really cold! Waterproof coats tend to be a bit more expensive than water resistant jackets!  A waterproof coat is guaranteed to keep you dry for a longer period of time- so that would be my first choice.  Whatever coat you choose, make sure the outer shell will keep water away! A waterproof/water-resistant layer on a jacket is what gives it warmth.

Windproof Material Gives A Coat Warmth

Did you know wind is a thief of body heat? Yep.  Wind is like the rogue middle child of Mother Nature.  No offense to middle children.  I’m a middle child myself.  But, I’m not a thief.  Wind is a thief and it takes your body heat and whisks it away, never to be seen again.  In fact, according to outdoor experts, we lose about 10%-15% of our body heat through the process of convection.  Convection is body heat lost through circulating air surrounding the body.

Have you ever noticed when it’s super cold outside, how weather casters will always mention the wind chill as well as the actually temperature? They do so because hypothermia and frostbite can take hold in a matter of minutes.  If you’re not properly dressed to withstand the wind and the cold all at the same time, you could die.  A jacket that is well insulated, waterproof and wind-resistance will keep you warm and able to stand outside for hours on end in frigid temperatures.

So, what makes a coat windproof? So glad you asked! It varies from brand to brand, but in general a windproof coat is made out of tightly woven synthetic fibers, designed to keep wind from penetrating the coat.  Some names or phrases you may see while coat shopping include: Polartec Windblock, Polartec Powershield, Paramo and Pertex. These are just a few names of windproof fibers that give coats the capabilities to ninja kick the wind and keep it away from your body.

Some waterproof coats are also windproof, but not all windproof coats keep water away.  Read the labels carefully before choosing the right coat for you.  Some outdoor experts say the more windproof the coat, the less breathable it becomes! Take that into consideration when trying to decide which outer layer will give you the most warmth for your planned outdoor winter adventure!

What Size Coat Should I Get?

Great question! The size of coat will determine how warm or how cold you will feel.  In general, you want to go a size up on your winter coat to allow extra room for all the layers.  You need a base layer to keep moisture away and mid layer to keep you body heat in check and then your outer coat to keep you comfortable and warm all day long! Try on a few different styles and pay special attention to the length of the sleeves.

It may sound silly but when you are trying on various winter coats pretend like you are doing the activity you’ll be doing in that coat.  You don’t want to find out half way up a glacier, the sleeves on your winter coat ride up and expose your wrists every time you re-position your ice pick in the snow.  See also our article “Should I Buy My Winter Coat One Size Bigger?”

Hood, Zippers and Thumb Holes

Once you’ve found the right fit for your warm winter coat, make sure you inspect the zippers and hood.  Even though a coat is waterproof and has the best insulation money can buy, the zippers can often be an afterthought.  Low quality zippers can be a perfect access point for wind, rain and sleet to slip inside and make you cold.  Higher quality coats, made from trusted brands, will often make an extra effort to make coat zippers waterproof too! This extra element is another way to make your winter coat extra warm.

Hoods also add extra warmth to a coat and to your body! A secure hood that fits around your face will keep your precious body heat from escaping.  Hoods with cinches are also a great choice because it stays in place, preventing more unnecessary heat loss. Coats with thumb hole liners will also keep you nice and toasty this winter.  Your wrists are home to some major arteries and when left uncovered, they can release a lot of body heat.  High quality jackets with thumb hole, keep a layer nice and secure over your wrists to cut down on heat loss!  If you ever feel chilled outside, cover your wrists! You’ll be amazed at how quickly you can take the chilly edge off!

Phew.  A lot goes into making a winter coat warm.  The right coat for you will depend on your favorite outdoor activities.  If you live in a colder climate, you may have a closet full of winter coats for various weather conditions, like I do.  A warm winter coat is an investment! It may be the most expensive piece of outdoor gear you buy- it’s certainly worth it!  Also check out our article “How To Dress For Winter Survival“.


Hi! I’m David. For most of my life I have been interested in emergency preparedness. Over the many years things have changed a great deal. From freeze dried food, to LED lanterns, preparing for an emergency has never been easier. The continual research I have done over the years have become the basis for this website. Now it is one of the most trusted sources to learn about emergency preparedness. Read More

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