Why Is Flannel So Warm

If you live in a cold climate like I do, then you definitely are familiar with flannel as a fabric.  But have you ever asked yourself the question why is flannel so warm?  It is just fabric, but yet it is so much warmer then say many other fabrics.

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why is flannel so warm - flannel fabric

I absolutely love flannel!   Whether it is flannel sheets, shirts, flannel lined clothing or just a flannel blanket, it is always my first choice in fabric.

I find that there is no other choice when it comes to choosing products that help keep me warm.

What is flannel?

When winter hits here in Canada everyone knows how cold it can get here.  As a Canadian, we are always looking for anything that will give us the upper hand in keeping our body and soul warm.   I am not kidding…..it gets darn cold here!   LOL!

With that cold spirit in mind, let’s look at what flannel really is.

Flannel is a fabric or material that has been used since the 17th century and is most commonly thought to have come from Wales.

Although the history is a bit mixed, some believe that it comes from the Welsh word “gwlanen”, meaning “woolen cloth”.  Many other believe that it actually comes from the French word “flaine”, which describes a coarse wool fabric.  Wherever flannel originated from, it has clearly been around and used for centuries.


why is flannel so warm - flannel manufacturing

There is often the misconception that tartar or plaid is the considered flannel.  That is simply not true.

Flannel was originally made from something called “carded wool”, or “worsted yarn”.  Today’s flannel fabric is actually made out of a mix or combination of wool, synthetic fiber, and cotton.  The fabrics are combined and then weaved in either a twill or plain weave.  This weave is then brushed using a metal brush that rubs the fabric in order to raise up the fibers.  Almost like “fluffing”
it up!


Why is it so warm?

When I talk about flannel and where it comes from, the way this mix of fabrics is weaved and then brushed goes directly to answering the question of why it is so warm.  Unlike other fabric, fabric is loosely woven, creating air pockets between the fibers.  These air pockets that flannel creates help us retain our own body heat there by keeping us warmer.

The production of flannel using the metal brushing technique and selecting cotton thread that is spun in a way to allow the thread to fluff up almost looking a bit “hairy”, makes for the best flannel fabric.


why is flannel so warm - flannel haircut


To add to this technique, the best flannel fabric once all fluffed up is then given what manufacturers call “a haircut”.  Or better explained as a being sheared.  The act of shearing the fabric after being woven actually causes the fabric then to have even more of a soft and fuzzy texture to it.   Along with this softer texture, you also end up with a high-quality flannel that won’t pill as quickly.  The slower pill speed creates a much warmer and softer flannel.


why is flannel so warm - flannel thread
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The brushed or raised fibers that is created with this technique when used, is what traps the heat in.  By trapping in the heat, this helps keep us warm and from getting any chills from the cold.  Another way it helps keep us warm, is that flannel fabric has weight to it.  It is this weight that is heavy and therefore definitely keeps us warmer.

We all know the saying, “You get what you pay for”!!

This saying is never more relevant then with flannel.  If you try to save money when purchasing lower quality flannel products, you will notice very quickly that the flannel will start to pill.  Now the act of pilling is when the flannel that is constantly rubbing against itself causes raised balls to appear on the fabric itself.  This causes the fabric to become lumpy and is a dead give away when wondering if the flannel you bought is of good quality of not.


How to stop pilling

When purchasing a cheaper flannel, which many of us do, simply because we can’t afford to buy as an example $400 flannel sheets, there are things that a person can do to try to keep their flannel from pilling.

Some of the easiest ways to stop your flannel from pilling faster, is to:

  • Before using the flannel, wash it without detergent and instead use 1 cup of vinegar, this rinses off the sizing or chemical additive that the manufacturer puts on the fabric
  • When washing your flannel, turn the garment inside out if possible
  • Use Woolite as the detergent when washing your flannel instead of regular detergent
  • Wash your flannel on the gentle cycle as it is a much slower speed, which helps protect the fabric
  • Never wash your flannel products in hot water, only COLD water
  • Don’t use liquid fabric softener when you are washing flannel, this causes the flannel fabric to actually break down and will cause excessive pilling
  • Use ½ cup of vinegar in the wash instead of fabric softener to help rinse away the detergent
  • When putting your flannel in the dryer, use a gentle or air-dry setting
  • Hang your flannel to dry when possible

All of these recommendations will absolutely help keep your flannel fabric products from pilling and looking great for an exceptionally long time.


why is flannel so warm - flannel pjs

Flannel products that keep us warm

When it comes to using flannel in a way to help keep us warm, we can do this many ways.

For example, things like using flannel sheets on our bed at night.  The warmth at night is something that can help provide a more restful sleep.  Everyone including myself, do not sleep well if I am cold.  Yes, you can choose to pile blankets on top of blankets instead of using flannel sheets, but then that becomes extremely heavy and uncomfortable.

why is flannel so warm - flannel sheets


Another way we can use flannel is in clothing like shirts or lined coats.  If you are heading outside into the cold, by simply putting on a flannel shirt over top of your t shirt or blouse, will provide an extra layer or warmth to your entire body.

If it gets even colder, by using flannel as a base layer underneath your clothes, will provide a type of extra insulation for you and help you to stay much warm.

One of my absolute favourite ways I use flannel to keep me warm, is with my pajamas.  Wearing flannel pajamas helps me to stay warm even before I head into bed.  Then once in bed, keeps me super cozy.  You can wear entire flannel pajamas, or just opt for the flannel pajama long shirt.  Don’t forget, when you get up in the morning, that throwing on your flannel housecoat, is also one great way to help keep you draft free.  All of these options absolutely help keep us warm in the wintertime.

why is flannel so warm - flannel pj's

I mentioned earlier that flannel is often used as a liner for coats, pants, and boots.  By using it as a liner in these products, it helps wick moisture away from our body which in turn keeps us overall much warmer.


why is flannel so warm - flannel line pants

Just think about it…..WINTER TIME.. That means snow on the ground. So, if you plan to go outside, that means trekking through the snow with your feet.  By wearing a boot lined with flannel, the moisture or sweat that is created by wearing the boots is wicked away from your feet and therefore keeps our feet warm and dry.


Flannel finale

Flannel to me is one of the greatest fabrics in the world.  Since I was a young girl, at the start of winter, I have always changed my summer sheets to my winter flannel sheets.  I would get so excited when that time would come.  I just knew that once those sheets were on my bed, I was guaranteed to sleep warm and cozy in my bed.

In my opinion there is no better choice then choosing flannel as one of the ways to help keep this prairie girl warm in our very cold Canadian winters.

why is flannel so warm - me and fergus

I hope you have enjoyed reading my post and that I have answered the question “why is flannel so warm”.  I would love to hear your comments and questions, so just drop me a comment below.  Stay warm!

2 thoughts on “Why Is Flannel So Warm”

  1. I absolutely love flannel.  I did live in Alaska for many years and it was something everyone has there.  I now live in Florida, and flannel to me is way too hot LOL.  Although I do love the feel of it, it is just not something I can wear here.  But I do have some flannel clothes for when I visit my dad in Alaska 🙂  It was interesting to read what flannel really is !

    • Hi,

      I completely understand that flannel certainly is not something to wear in Florida.  I think that living in Florida would far out way my love of flannel too. LOL! Lucky you.

      It is already starting to get cold here and as I sit writing back to you, I am wearing a flannel shirt.  In Western Canada, we certainly need all the help we can get.

      Thank you for sharing your love of flannel with me, I really appreciate you taking the time.

      Enjoy your sunny warm weather.  I am super jealous already.



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