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Thermal Fabrics: Keep Hot Hot and Cold Cold

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Years ago the Thermos® company had the slogan, "Keeps hot things hot and cold things cold." You can't say it much better than that. Did you know there are fabrics that help you do the same thing? These aren't the heavy industrial materials that keep steelworkers, astronauts, and firefighters safe, but honest-to-goodness fabrics you can actually sew with. 

Thermal fabrics are useful for all kinds of projects where you want to keep hot stuff hot and cold stuff cold, such as pot holders and oven mitts, table pads, lunch carriers, shopping totes, ironing board pads, outdoor stadium cushions, tea cozies, and many other items.

The options fall into three basic categories: 

  • Thermal Batting, which has insulating properties.
  • Thermal Fabric, which can withstand high temperatures without scorching.
  • Thermal Interfacing, which is a lighter weight insulating option.

An important note about microwaving: The materials listed below that have a metallic layer specifically say, "Do not microwave." None of the rest actually state they are safe to microwave either. So for any kind of thermal fabric, unless it specifically says it's microwavable, we recommend you don't risk it. One exception, described at the end of this page, is Wrap-N-Zap by Pellon, which is specifically designed to be microwaved.

Thermal Batting


The most versatile thermal batting product we found (and use quite often here at S4H) is Insul-Bright from The Warm Company. It's made with hollow, polyester fibers that have been needle-punched through a nonwoven substrate, and then through a reflective metalized poly film. The needled material is breathable. The hollow fibers insulate by resisting conduction. And the metalized poly film resists radiant energy by reflecting it back to its source.

Insul-Bright is machine washable, easy to cut to size, and apart from being just a bit slippery, is quite nice to work with. Most sources offer it by the yard in 22" and 45" widths, and a few outlets offer 36" x 45" pre-cuts. 

Even though we've listed this material in the 'batting' category, The Warm Company does suggest you layer Insul-Bright with a standard cotton batting if you are using it for a high-heat application.

A number of sources offer Insul-Bright online, including Jo-Ann and It's also readily available at many local fabric and craft stores.


This space-age thermal batting from The Warm Company was originally designed for insulating air conditioning ducts or wrapping your hot water heater. But Insul-Shine is actually quite sewable.

You can make something simple, like a reflective visor for your car or to put in your RV windows to prevent sun damage. If you're looking for a mod metallic look, you could also use it to cover a headboard, throw pillows, or make a budding astronaut very happy with some rocket wall art.

Insul-Shine has two layers, reflective material and insulating polyester batting. It is washable, but doing this may dull the reflective side. Sold in 22" and 45" widths.

You can find it at and among others.


Also made by The Warm Company, this thermal batting is very similar to Insul-Shine, but Insul-FAB has an additional layer of white lining-style fabric. It's a good solution when you want a smoother and more comfortable finish on the interior of your project. 

It's also machine washable. We found Insul-FAB by the yard in a 22" width at and

Thermal Fabric

Iron Quick

Iron Quick is a specialty fabric made of 100% aluminum with 100% cotton backing. It's designed to protect from heat (up to 399˚), but does not have any insulating properties. Sold by the yard, it's 45" wide and machine washable.

When you need insulating as well as heat protection, Iron Quick also comes as a quilted material. This is simply the regular Iron Quick fabric with a 100% cotton backing, polyester batting, and polyester/cotton backing. This doesn't afford a huge amount of insulation, but you could use more than one layer. It is only 42" wide.

Neither Iron Quick products should ever be used in the microwave.

They can be machine washed but should be air dried. You can also use a damp cloth to wipe clean.

Nancy's Notions carries both types of Iron Quick products by the yard.

Therma Flec

Therma Flec is a lightweight, heat resistant cloth similar to the Iron Quick but made from 80% cotton/20% polyester. It is scorch-proof to 390˚, and like the Iron Quick cloth, does not provide insulation. But also like the Iron Quick, you can find it in a quilted version for items such as hot pads, oven mitts or ironing board pads. Both the flat cloth and the quilted option are available in two colors: silver and light gold, all in a 43-44" width. Again, don't put this product in the microwave.

We found Therma Flec, in both colors, several places online, including and OnlineFabricStore.

Thermal Interfacing


Back in the 1980s, the 3M Company introduced an amazing new insulating material called Thinsulate. Ounce for ounce it had one and a half times the warmth of down and twice the warmth of other high-loft insulation materials. It meant you could get cool looking ski gloves that were just as warm as giant, puffy mittens.

A quarter century later, Thinsulate is still amazing. Made from microfibers that are only a tenth the size of of other synthetic insulation, it's much more effective at reflecting back heat. And Thinsulate absorbs less than 1% of its weight in water, allowing it to retain its insulating ability even in damp conditions. You can use it in any kind of project where you want to keep warm but don't want a lot of bulk, such as jackets and blankets.

Thinsulate is machine washable and dry cleanable once you have sewn it inside your project. It is a bit tough to find as yardage, but we did locate Thinsulate online at Vogue Fabric Store. It's available by the yard, 60" wide.



Pellon makes a 100% polyester interfacing called Thermolam, which is a needle-punched, sew-in fleece with a protective scrim that can provide some warmth. It's available by the yard at a 45" width and is machine washable. It's considered a heavy-weight in the general world of interfacing, however, it doesn't have any loft, so it isn't a choice for projects that call for true insulating and/or padded properties.

There's no microwave warning for this fabric, but then again, I couldn't find anything that said it was okay to use either. Maybe you should just forget the microwave, huh? offers a good price on Thermolam by the yard as does


Wrap-N-Zap by Pellon is the only thermal product mentioned on this page that we can safely declare to be microwave safe. It's got Zap in its name and it says "Microwave Friendly!" right on the package.

Made from 100% cotton batting, Wrap-N-Zap is designed for projects like insulated baked potato bags and casserole warmers – situations where you heat up the food inside the cover and leave it on to keep it warm.

You can machine wash Wrap-N-Zap after you've sewn it into a project, but you should only use cotton fabrics, threads, and trims to insure it retains its microwave-safe designation. 

We found it in a 45" x 1 yard package at JoAnn Fabric. You can also find it online at Nancy's Notions and

Thermal fabrics are a "hot" trend

When we first researched this topic several years ago, we could only find about four kinds of thermal fabric or batting that was sewable and relatively easy to locate as yardage. Now we're finding a lot more options. And we didn't even include all the new energy-saving materials you can sew into things like super thermal window shades. It's nice to see the selection growing. 

Be adventurous and try some projects that are made to keep hot things hot, and cold things cold. Below are a few recent Sew4Home projects to get you started:

Casserole Carrier

Insulated Baby Bottle Carrier

Lunch Bag

Picnic Tote

Hot Pads

Oven Mitts


Comments (52)

Bishop said:
Bishop's picture

Thanks for the article. I read all the discriptions and it seems most these fabrics are decribed by keeping warmth "in". Would you be able to reccomned one for keeping the warmth "out" or the cool "in". I am having a custom made patio tent made for the back of my camping trailer. It will be completely enclosed. I need a to find a good material for keeping the cool A/C air inside this tent and reflecting the outside heat. I was interested in the Thinsulate for it's lite weight. Would it be as simple as turning it around to reflect heat back out of the tent?

Thanks for any help you guys could provide. - B.

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

@ Bishop - as we mention above, the idea of these fabrics is both to help keep hot things hot and cold things cold. They are all designed to reduce conduction. So, yes, they could certainly work for your situation. What you're describing sounds like a large area and a custom job (certainly nothing similar to what we've done with our small home décor projects), so we really can't advise long-distance which product would be best for you. Perhaps discussing the options with the person doing the custom work for you would be a good idea. 

CeeGeeGee4 said:
CeeGeeGee4's picture

Very frustrated looking for puffy quilted fabric to make a lightweight short coat or ski jacket  possiboy in bright neon shade that will pack easily.  Any sources?  Thanks!

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

@ CeeGeeGee4 - we don't really focus on clothing construction here at S4H and so may not be your best source for answers. But, there is one local company we use regularly for strapping, buckles and clips: The Rain Shed - they specialize in outdoor fabric and supplies and do carry some insulation. If they don't have what you need, they may be able to help point you in the right direction:

Nicole Heatherington said:
Nicole Heatherington's picture

Which product, if any, would be best to use to line cotton curtains to block out the sun's heat?

Jane Doenut said:
Jane Doenut's picture

Hi. Thank you for your great article. Please, maybe you have some suggestions for me too? I need help on a project I'm planning on doing. I am making a denim and quilting cotton floor cloth for my 'Glamper' to put across the entire floor space over the carpet. It gets very cold in at night and I would like back my pretty floor cloth with denim but I need to find the absolute best affordable solution for the middle with or without additional batting. Every layer is a good thing for drafty -15 degree nights during winter camping. I was thinking about Thinsulate but maybe you have a better suggestion?

Thank you.

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

@ Jane Doenut - that is a very specific use that we don't have specific experience with. Your thought about the Thinsulate makes sense as that is the option most associated with outdoor gear. You might consider two layers of Thinsulate or perhaps a layer of Thinsulate along with a layer of batting. You also might consider visiting the website for The Warm Company who makes much of the regular thermal batting. They have a Warm Window product that might be a good option for your project:

Jane Doenut said:
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Thank you for taking the time to respond. I will do some comparative research between the two and go from there. Many thanks for the tips.

Charles said:
Charles's picture

This is a great article, but I am still looking for something a little more specific. Maybe you guys can help...

I would like to make a high quality barber towel.  Standard barber towels in the us are made of 100% cotton herringbone fabrics, but I would like to have something maybe a little better quality.

Basically the caracteristics would be that it maintains moisture and heat while on the clients face to soften beard before the shave.  Although many barbers have heating cabinets, some use microwaves, therefore 100% cotton is the best.  What I'm not quite sure about is if the Pollen brand products can because the might ought to be used with another material to cover them.

If you anyone has any suggestions, it would be greatly appreciated.

Charles said:
Charles's picture

Hello again, I was thinking that maybe I should just find a good quality terry cloth instead.  What are your thoughts?

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

@ Charles - interesting challenge. As you mentioned in your first comment, 100% cotton is likely your best bet. And, yes, a high quality cotton terry cloth would be great. That said, the thicker cotton terry cloth can be hard to source. We haven't worked with the Pollen fabrics. I believe they are hemp/wool blends. I'm not sure how that would perform with the heavy mositure. Your best bet is probably to continue your search and then get small cuts of the best options you find. Put the swatches through the exact situation you plan for the finished towel and see which performs best. 

Eliza Fox said:
Eliza Fox's picture

Hi there! I'd actually recommend hemp fiber over cotton because it retains more water than cotton. You can buy hemp terry, French terry, jersey, other knits/wovens; there's a lot of variety. The amount of water it will hold onto is ideal for what you're talking about even though it is not thick. It's a really amazing fibre and I've actually made cloths for my dad for precisely the purpose you describe and he loves them. 
Here's a source I recommend:

Eliza said:
Eliza 's picture

Oh, I forgot to mention you can also get a sample box of their fabrics as well as a swatch set. 

Charles said:
Charles's picture

Eliza looks like a good option for me.  Could you tell me which fabric you used for your father's "towels". 

Holding water is great, but also the ability to hold heat and have a bit of texture to actually clean the face and not slide right off when shaving product is on the face.

Thank you in advance for your advice!


lb.again said:
lb.again's picture

Is there a fabric that is best to keep cold drinks cold in a fabric coozie? 

Camille S. said:
Camille S.'s picture

Thank you for this information.  It's quite helpful.  I'm considering a new project that requires "heat-resistant fabric" but had no idea how to find it without product names.  I'm going to bookmark this site for future reference.

Patricia OK said:
Patricia OK's picture

I am looking for a 'blanket' type fabric that I can use under a tablecloth to protect my table.  I don't like the 'plastic' type pads that are sold everwhere, I want something that will hang more over the edge of the table but also prevent it from scratches and a certain amount of heat, although I wouldn't put anything very hot on it.  Any suggestions as to what would be best?

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

@ Patricia OK - I think the Thermal Fabrics described above are what you are looking for. There are links to where-to-buy options for both.

shahin113 said:
shahin113's picture

hi i am looking for thermal fabric that will create heat when tempreture is cold and will cool down when it is hot. Iam doing this project where i want to create football boots which will adjust to hot or cold depending on the temreture.

if you have any ideas it will be great to here them.

 thank you!

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

@ shahin113 - as we mentioned above, the type of thermal fabrics we reviewed are designed to insulate by resisting conduction. The metalized poly film resists radiant energy by reflecting it back to its source. The can't create heat or cool on their own; they can only insulate. If something is already warm, it can help keep it warm - if it's already cool, it can help keep it that way. You would need an additional outside source of engergy to actually create a dramatic change in temperature - such as an ice pack to cool something down or those chemical hand warmers to create instant heat. In some of the extreme outdoor clothing offerings, there are some materials with wicking capabilities or other features that can further impact temperature, but we don't deal in those type of projects and so do not consider ourselves experts in that arena. 

SamIam said:
SamIam's picture

I am beyond words....this site has me totally wound like a spring to put the needle and thread to work.

John said:
John's picture

What are some of the new energy-saving materials you can sew into things like super thermal window shades?

That's exactly what I'm looking to do, and while the things you listed are helpful, I'd love to know what else is out there.

Thanks for this list!

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

@ John - our goal with this article was to outline the more widely used and available insulating materials. It sounds like you are doing the right thing by searching online for more targeted information about your particular use. That's certainly exactly where we would start. You might want to check out Warm Company (they make several of the products listed above) in more detail. They offer an actual Warm Window option.

Jeanne said:
Jeanne's picture

I would apreciate your help. I have been looking for a fireplace blanket to attach to my fireplace at night after the fire has gone down to prevent drafts from coming down the chimney. I have seen them advertised on the Plow and Hearth website but can't find the correct size. Would any of these fabrics be safe for me to use in such an application? The ones I have seen are made from a fabric called Pavenex and attach by magnets to the fireplace screen frame. I can sew and could easily make one to my size specifications if I could find the proper fabric to use. Thank you for your help.

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

@ Jeanne - I'm sorry but that is not a fabric we came across in our research, so we don't have any resources for you. When dealing with fire, we would hate to give you a recommendation without having tested in that situation. You might try reaching out directly to the manufacturers (such as Warm Company) for their more expert advice. 

Dogmore said:
Dogmore's picture

Hi great info here thank you for that.  I have a question; I am thinking of designing/sewing a custom form-fitting jacket/sweater for my dog using Thinsulate (based on your info above seems like the bet choice for my project), but I also need the material to be stretchy.  Is Thinsulate have any give to the material or has any stretchness to it?  If so, great!  If not, what materail would you reccomend for warmth that can stretch?  If it helps, I'm looking to do 2 jackets; 1 that is for warmth and the other serving as a cheap way to hair.  So I presumme these will be two different matrerials due to cost.  Please, any advise on materails you reccomend is GREATLY appreaciated. 

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

@ Dogmore - None of the products have a huge amount of stretchiness to them. You are correct that the Thinsulate is likely to have the most give; it is the one most used within garment manufacturering. Other than that, you might even look at just a traditional wool for warmth. Not necessarily the cheapest, but certainly warm, flexible and easy to work with. 

pmhz said:
pmhz's picture

Is fleece safe to use as the material for hot packs filled with feed corn?

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

@ pmhz - cotton is the best option for packs you will be using in a microwave. We did make one sample that was cotton ticking on one side and fleece on the other for a rice filled warming pad. That worked well, but it was designed to need to heat only about two minutes. Because fleece is not a natural fiber, you could want to make sure the heating times requried were low. I've included links below to the original tutorial as well as our tutorial on fillers:

imchris said:
imchris's picture

I want to make a self-warming pet bed, like some that I have seen online. It seems they use a layer that is supposed to reflect the body heat of your pet back towards them, thus self-warming. As far as I can tell a few of these products look promising to use as a heat-reflecting layer of the bedding, does anybody have a suggestion about a specific product to use?

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

@ imchris - this isn't a useage we've done any testing with. It does seem the products with a reflective layer have the most potential for working - probably the Insul-Shine as the most likely. Perhaps before buying a huge amount or jumping into the full project, you could buy a smaller square of it to use as a layer within your pet's regular bedding to see if it creates the warming effect you're hoping for. Many places do offer it for sale by the yard.

anonymous said:
anonymous's picture

I am confused on the comments about microwaving. Could you explain to me what the importance is? Thank you!

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

You cannot put metal into a microwave. If you are making a project you intend to be able to be mircrowaved, such as a warming pad, you need to make sure you are not using a metal based batting. If you are not making something that will not be mircrowaved, then you can use the metal based fabric.

Petson said:
Petson's picture

Thanks for the information from the last couple of days I was searching for this, Do you think reflective insulation will be going to help me to keep my house at normal temperature.

Anthony Antoneli said:
Anthony Antoneli's picture

Hi, I am looking to sew a thermal fabric in an 8" diameter cylinder that would keep in the heat and not escape.  What would you recommend as the best fabric for this.

Thank you.

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

@ Anthony Antoneli - there are a lot of variables regarding the exterior fabric(s) you're working with, other interfacing, exact useage, etc. - so we can't give you a guaranteed recommendation. But if it's a simple thermal container, the Insul-Bright, Shine or Fab would all work well. In the smaller space, the Insul-Bright may be the easier to work with. 

Marcus said:
Marcus 's picture

Hi id like to make some surfboard cover bags, is this available in australia?

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

@ Marcus - you didn't indicate which product you were wondering about, but in any case, I'd suggest googling by the product name to find the best options to buy in Australia. It is carried on several fabric sites, many of which do ship internationally, but of course it would be much cheaper to buy locally. I don't know of any reason why it wouldn't be available to you.

George B said:
George B's picture

I want to insulate our open to the bedroom shower and sink area to retain heat from Dietz kerosene lanterns in shower. We never use our heater and I want morning showers to not be freezing events as I get wet, turn off water to soap and scrub, rinse and then quick alternate hot water and cold with icy cold water final rinse. The shower has a window which I leave open about 8 inches at all times for ventalation. I just want the bathroom area to be warm. I was thinking ceiling to floor thermal curtains to keep the heat in?

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

@ George B - This is really more of a question for an insulation expert rather than a sewing person. We don't have the expertise with your type of heating or the knowledge of the room to really know if curtains are your best bet. They can certainly be made and there are many good thermal fabric options you could use in tandem with a blanket weight poly or wool. Best of luck staying toasty.

Jen Mansfield said:
Jen Mansfield 's picture


Do you know which thermal material is best for an insulated lunhc box if you don't want to have to use a liner over it. We don't want it to be fuzzy - we would love to find that silver liner used in reuseable cold food bags. Thank you!

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

@ Jen Mansfield - we haven't done a lunchbag without a lining over the insulating material. I don't think that would be my first recommendation. The InsulFab or InsulShine sound most like what you are describing, however, I just don't know how they would hold up against wetness or pokes/tears without a lining. The thermal fabric might be a better choice if you really don't want to use a lining. But, really, without having tested this situation, I can't give you a 100% guaranteed recommendation. You might need a bit of trial and error. 

Nina Daub said:
Nina Daub's picture

Thank you for this tutorial.  I would like to know which product to use to keep things cool.  Is there one better than the other?  

Liz Johnson.Editor.Sew4Home said:
Liz Johnson.Editor.Sew4Home's picture

@ Nina Daub - the concept is the same for retaining either hot or cold temperature. You don't need the anti-scorching properties of the thermal fabrics, but you do need the insultating properties. So any of the products with insulating capabilities could work, depending on the project. If you are needing to keep something very cold (or very hot) you may need to consider more than one layer of insulating product. The other factor will be how well your project is sealed - the tighter the seal, the better the insulation.

KarinJ said:
KarinJ's picture

Outdoor Wilderness Fabrics is awesome. Large outdoor fabric selection, and very, very affordable. Thank you for the link!

daisygirl said:
daisygirl's picture

I learned about Insul-Bright from sew4home and  made hot pads and oven mitts for my family and friends. Thank you for your great ideas!

I'm agree a tutorial for car windshield sun visor will be just in time for next hot summer.


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