Dritz_2016_Leaderboard_Visit Dritz

Facebook Twitter Sew4Home RSS Feed Follow Me on Pinterest Instagram

Sew4Home

Keep Hot Hot and Cold Cold with Thermal Fabrics

Printer-friendly versionSend by emailPDF version

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.

And, because of the metallic coatings common to many of types, and the fact that they're easy to sew, you can even use them to make some pretty creative costumes – from medieval armor to Lady Gaga!

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

Insul-Bright

The thermal batting product that's been around the longest 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.

It contains no resins or glues and will not shift, migrate, or bend. You could use it in clothing, but it would be rather noisy. However, babies and animals often love the noise and like to scrunch it up in soft books and toys.

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 considering two layers or layering 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 Fabric Depot, Jo-Ann and Fabric.com. It's also readily available at many local fabric and craft stores.

Insul-Shine

This space-age thermal batting from The Warm Company was originally designed for insulating air conditioning ducts or wrapping your hot water heater (for which it's very effective). 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. The metal surface wipes clean and actually acts as a water barrier for soft coolers, diaper bags, and bottle carriers.

It is washable, but doing this may dull the reflective side. Sold in 22" and 45" widths.

You can find it at Amazon and Fabric.com among others.

Insul-FAB

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. 

Because it's designed not to show the insulation, it's perfect for insulating totes, lunch sacks, casserole covers, and more.

It's also machine washable and dryer-safe. We found Insul-FAB by the yard in a 22" width at CreateForLess.com and in a 45" width at Fabric Depot.

Solarize

Solarize, a new thermal product by Fairfield, is a uniquely thin metallic insulating fabric. Less noisy and crinkly than other offerings, Solarize still creates a strong thermal barrier that keeps things hot or cold. And it works with the shiny side in or out – you choose. Keep the shiny side exposed to help conduct heat or reflect light. 

It is a sew-in product, made of 50% polyester + 50% aluminum, and the standard width is 22”. You can purchase it as yardage or get it in a “grab-and-go” pre-cut package of 22” x ¾ yd.

Use Solarize inside pillows, fabric scarves, mittens, jackets, hats, and blankets for added warmth. Add it to casserole carriers, potholders, and trivets.  Cool things down by Solarizing inside can cozies, thermal freezer bags, or ice pack wraps. 

You can purchase Solarize directly from Fairfield or find it Walmart and other retailers. You can also buy full bolts from Amazon.

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 so it's long been the go-to choice for things like ironing board covers. 

When you need insulating as well as heat protection, like in your oven mitts, Iron Quick also comes as a quilted material. This is simply the regular Iron Quick fabric with a 100% cotton backing, plus polyester batting and a polyester/cotton backing. This doesn't afford a huge amount of insulation, but you could use more than one layer or add a layer of regular or thermal batting. 

Both varieties come in the same 45" width. When sewing, you should use a size 80/12 needle. 

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

Both can be machine washed but should then be air dried – not tossed in the dryer. 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 360˚, but like the Iron Quick cloth, does not provide insulation. However, also like the Iron Quick, you can find Therma Flec 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. Don't put this product in the microwave.

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

Thermal Interfacing

Thinsulate

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 sleek 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.

You can get varying densities of Thinsulate, depending on the weight and R-value (insulating property) you want, from 1.6 up to 2.9.

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 and The Rain Shed. It's available by the yard, 60" wide.

Thermolam

 

Pellon makes a 100% polyester interfacing called Thermolam, which is a needle-punched fleece with a protective scrim that can provide some warmth. It's available by the yard at a 45" width as both a sew-in or a fusible 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 high-level insulating and/or padded properties.

There's no microwave warning for this fabric, but then again, we couldn't find anything that said it was okay to use either. Maybe you should just forget the microwave, huh?

Fabric Depot offers a good price on Thermolam by the yard (both sew-in and fusible). 

Wrap-N-Zap

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, without glues or other chemicals that could leach into foods, 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 the cover on to keep food 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 full microwave-safe designation. 

We found it in a 45" x 1 yard package at Joann Fabric and Nancy's Notions.

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 Sew4Home projects to get you started:

Casserole Carrier

Insulated Baby Bottle Carrier

Lunch Bag

Picnic Tote

Hot Pads

Oven Mitts

Two-Handed Potholder

Section: 

Comments (44)

Jamesrh said:
Jamesrh's picture

I think all of your information is great! I am wondering if you know of any companies that can do custom cutting/sewing work for a project that my office needs. Also, can you say if any products that you've tested would be better than others at being heated to 150° or so constantly? I appreciate any information you may be able to provide. Thanks!

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

@Jamesrh - Thank you. For cutting/sewing work, you should search in your local area under "contract sewing." We haven't tested any of the materials at 150˚ for consistant times and so can't give you advice on that. You might be able to reach out directly to the manufacturers to see if they have specific test results. 

Jamesrh said:
Jamesrh's picture

Thanks for your response, I will continue to research for our project. If I learn anything interesting, I'll let you know!

Susan Taylor said:
Susan Taylor's picture

The pipes on my motorcycle get really hot and burn the inside of my leg.  I'm looking for fabric I could sew into my jeans or chaps that would provide some protection from the heat. Any suggestions?

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

@ Susan - We're always a bit reluctant to give suggestions on specialty situations we haven't experimented with, but in general, it seems like you would want something like the Thermaflec that woud be more "fabric like" and so could mold to your exterior jeans or chaps. Perhaps someone at a local motorcycle shop could provide more expert advice. 

Amit sharma said:
Amit sharma's picture

Hi

Can anyone tell me the fabric name for keeping water cold for drinking purpose and where to buy.

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

@ Amit - Sorry, we do not have any formation on fabrics that could be used to directly hold water (like a water bag). All the insulation materials we've seen are for keeping a container of water cool. 

Jonathan said:
Jonathan's picture

Hello,

I am looking for a heat reflective fabric that I can put on my child's car seat.  In the summer, the car seat gets terribly hot and makes sitting in uncomfortable for my child.  Any recommendations?  

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

@ Jonathan - No fabric is really perfect for that on a DIY scale, although some people really like terrycloth. It's pretty hard to make the heat go backwards into the seat. One of the most popular things I've seen out there is a child's car seat cover with a series of horizontal pockets into which you can slip ice packs, like you would use for a lunchbox. They seem to keep the seat cool for a number of hours while out and about. We don't have a project for that here, but if you search in Google or on Pinterest, you'll find quite a few. 

Jonathan said:
Jonathan's picture

@Liz - Thanks for the reply.  I'm not intending to make the heat go backwards into the seat.  What I am after is a fabric that will reflect the heat (especially if the sun is beating down on the seat). Perhaps something like Solarize?

Out of curiosity, why do people like terrycloth?  

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

@Jonathan - Anything that reflects is still gong to be absorbing some heat as it reflects - think of it like those shades you use across the windshield. That material helps reflect the light and heat, but I don't think you'd want to sit on it. These are great products for helping keep in the hot or cold, but as I mentioned, there really isn't anything that I know about that can both help reflect the heat and light white still keeping itself cool. That sounds like a job for NASA I think . A lot of people use terry towels becaues they are usually all cotton and do a good job of absorbing heat without getting too hot and sticky. But even they eventually get hot - just not as hot as plastic seats. Take a look at those cooling pouch car seat covers; they look pretty interesting. 

Mpaltura said:
Mpaltura's picture

Hi! I want to make a case to put around a hardshell flute case.  I want it to keep the flute from getting cold and to protect it from the heat if it were to be left in a car.  What materials would be good to use to make a flute case??

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

@ Mpaltura - Wow - a flute is an important thing to keep protected. We don't really have the expertise with that sort of specialty use to know what would be best. I'd hate to give you the wrong recommendation and possibly damage your instrument. There are also several variables that would come into play, such as how much protection the main case provides as well as how hot and how cold you are protecting against. It would probably be best to ask this question of someone who specializes in traveling cases for musical instruments. 

Warren Dorer said:
Warren Dorer's picture

I am a leather artist. One of the products that I make are wine carriers. I am looking for a thin product that will both insulate and cushion a wine bottle preventing sweating or breakage. Your thoughts?

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

@ Warren - We don't work much with real leather, so don't really know all the ins and outs. In general, finding one product that can do all those things is likely to be a challenge. The thermal battings aren't really meant to have any water resistant capabilities. You may need a series of layers. The Fairfield Solarize product is by far the thinnest as a thermal barrier. You might consider sandwiching this with a plain or quilted batting and a PUL type barrier on the inside. Fairfield (and others) also have a PUL product. There is theirs: https://www.fairfieldworld.com/store/category/shield-liner-fabric-craft-...

You can get both the Solarize and the Shield in small, fairly inexpensive sample paks, which would be a good way to do a test.

Warren Dorer said:
Warren Dorer's picture

I am a leather artist. On of my products is a single/double wine carrier. A wet or sweating cold wine bottle might bleed thru my leather causing damage. looking for a fabric that I can sew to the leather prior to construction to alleviate this potential problem. Your thoughts?

NewSewer said:
NewSewer's picture

im looking for a wide fabric that is reflective to make a shade cover on my sailboat. A friend had one made, but I've found those who make canvas for boats don't want to give up their secrets.  Has anyone seen anything like this?  It really reduced the heat underneath his cockpit canvas significantly.

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

@NewSewer - I'm afraid that's a specialty issue we don't have any familiarity with. You might try reaching out directly to The Warm Company who makes several of the these thermal batting products. Perhaps they have a more "industrial" width/option they could share with you. 

https://warmcompany.com/

JPKnox said:
JPKnox's picture

Which would be best for a fish bag or game bag?  I fish and hunt alot and I would like to build my own bags that fit into my boat and truck for a true custom fit.  

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

@JPKnox - If we haven't tested a project, we can't really give you a guaranteed recommendation. In general, something a bit thicker would probably be best, such as the Insul-Shine or Insul-Fab. Since you are likely out and about for lengthy period of times, we might also recommend a layer of the Solarize as well. Then, you'd want to use something to line the whole thing that is water-resistant because of what you are carrying - maybe PUL or ripstop nylon.

R Frank said:
R Frank's picture

What is the maximum temperature for the Solarize product?

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

@R Frank - That information was not provided to us, but I'm sure you could reach out directly to Fairfield (the manufacturer) and inquire about their testing results: https://www.fairfieldworld.com/

Judi said:
Judi's picture

I am wanting to make the wallets/purses to form a protective layer for passports and credit cards.  Would you recommend any of the these fabrics?

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

@Judi - I do know that the folks at Fairfield were testing their Solarize product to see if it would quality as a protective layer, but we haven't heard an update on that lately. You could reach out to them directly: https://www.fairfieldworld.com/

Crystal Bai said:
Crystal Bai's picture

Hi there! Thanks for such a wonderful comparitive article! I want to make a lunch bag that can be dual functional for cold and hot items. (or if even better, have two sections) Which material is the higher quality and best fit for the purpose in this case?

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

@Crystal - There are a lot of variables regarding fabric and the pattern you plan to use, so I can't give you a "for-sure" recommendation, but the Insul-bright would probably be my first choice, Possibly in combination with the Solarize if you have "sections" that might need something thinner. 

Kygr said:
Kygr's picture

which would you recommend for a blanket? My mom stays cold ALL year long and I want to make her a blanket for her bed.

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

@Kygr - For a blanket, probably only the Solarize or the Thinsulate would make sense, and even then, I would recommend focusing more on the outer fabric itself, and would still add a thicker cotton batting as well. Maybe look at fleece for its softness, perhaps with a flannel backing. The other thermal options can be bulky and with their heat resistant layers are rather noisy or crinkly -- not good features for a blanket  

Sassy Lady said:
Sassy Lady 's picture

Could you use this material to make clothing. I am looking for womething to make some items for the homeless for winter time. Itms such as shirts, pants etc for those that sometime have to sleep in cardboard boxes etc.

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

@Sassy Lady - these materials are really designed to go within layers of standard fabrics. You could certainly use them in that manner to help further insulate an already warm fabric, like fleece or wool or heavy denim. Since we've never tested it, I don't really know how well they'd react to the elements on their own. In general, I think they'd be rather bulky and noisy. Insulating standard clothing would likely be a better option. 

denise HOSNER said:
denise HOSNER's picture

Can you use insul-brite in a cold water bottle bag without sandwiching it between 2 fabrics..so you see the silver in the bag?

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

@ denise - you could do it that way, but we usually recommend a lining. Because cold bottles can "sweat" a water resistant lining is best, such as rip stop nylon or PUL.

Theresa M. said:
Theresa M.'s picture

This is great infformation! I have a couple of bag patterns that I would like to convert to insulated-type totes by using some insul-bright. Do you know if you get additional insulating properties by adding more layers of the insul-bright? I'm thinking of cooler-type grocery bags to use when I go to the store and stock up on frozen and cold items so they don't melt before I get them home.

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

@ Theresa - Yes, additional layers does provide additional insulating properties. I don't have the technical information from any of the companies to say exactly how much (ie. if it doubles, etc.) but it does certainly help. Many people prefer two layers on any hotpads as a rule.

eh.struble said:
eh.struble's picture

Really wish there was a link to a car screen tutorial :/

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

eh.struble - we don't have anything like that currently on the site, but we will add your suggestion to our You Asked 4 It list. 

Diane Beavers said:
Diane Beavers's picture

Thank you so much for this post. I've been seeking hot/cold insulators for my lunch totes and now i know exactly what to use and where to buy it.

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

@Diane - Great! That is exactly what we hoped would happen 

DebS said:
DebS's picture

I agree with JudysPod - very detailed and informative. I will save this for future reference. As the saying goes, there's always something new you can learn. Thanks again, Sew4Home!

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

@ DebS - Thanks! If's always been a favorite article and it was fun to go through and update with the latest news.

JudysPod@gmail said:
JudysPod@gmail's picture

Thank you for this information, best summary I have seen....

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

@ JudysPod - Thanks! Always glad to know we've been a help.

Amit sharma said:
Amit sharma's picture

Plz tell me the fabric name which can keep water cold for drinking purpose.

Add new comment

*Sew4Home reserves the right to restrict comments that don’t relate to the article, contain profanity, personal attacks or promote personal or other business.
By submitting this form, you accept the Mollom privacy policy.