How to Do a Fabric Burn Test

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Learn how to do a fabric burn test so that you can figure out the fiber content of the fabric. It’s great for that mystery fabric in your stash!
Sometimes you get fabric when someone cleans out their stash. Sometimes you thrift fabric. This kind of fabric is rarely marked with the content, but a fabric burn test can help you figure it out.
Now it’s impossible to figure out exactly what kind of fiber the fabric is made from, but you can find out if it’s a synthetic, natural, or blended. If you need a refresher, all about fabric to learn the basics.

How to Do a Fabric Burn Test
Supplies
- Small pieces of fabric with unknown content
- Small pieces of fabric with known content for comparing
- Metal container to hold burning fabric
- Matches or a lighter
Questions to ask while burning
You are going to burn your fabric scrap and ask yourself some questions along the way:
- How is it burning? Does is melt and bubble or burn?
- How does it smell? Does it smell like plastic burning or does it smell like hair burning?
- What color of smoke does it give off? Is it black or white?
- What does it look like afterwards? Is it like ashes or like hard melted plastic?
- If the fabric is burning, it is a natural fiber. If it smells like a regular fire and gives off white to gray smoke, it is a natural fiber. The burned bits were ashy.
- If the fabric melts when it burns, it is a synthetic fiber. If it gives of a unnatural smell, like burning plastic or rubber, and gives off dark smoke it is a synthetic fiber. The burned bits will be hard.
- If the fabric does a little bit of both, it is a blend.
Cotton Spandex Jersey
Burned, smelled natural, white smoke, and ashy
Bamboo Rayon Spandex French Terry
Burned, smelled natural, white smoke, and ashy
Wool Blend Coating
Burned, smelled natural, white smoke, and ashy, but there was also some melting and dark smoke. I think this is a blend.
Unknown Fuzzy Sweatshirt Fabric
melts, unnatural smell, dark smoke, and it’s hard after burning
Cotton muslin
Burned, smelled natural, white smoke, and ashy
Unknown slub fabric
melts, unnatural smell, dark smoke, and it’s hard after burning
Silk
Burned, smelled natural, white smoke, and ashy
Unknown silk-like fabric
melts, unnatural smell, dark smoke, and it’s hard after burning
Acrylic craft felt
melts, unnatural smell, dark smoke, and it’s hard after burning
It is easier to tell when you compare the pieces after they’re burned. Now this isn’t a foolproof method, but it’s better than not knowing! I found a really handy fiber burn chart to help answer more questions!
If you make something using this tutorial, I’d love to see! Please share it on social media with the hashtag #heatherhandmade and tag me!
I believe small sewing moments can create great joy. Find your own “right” way to sew. -Heather
How I wish I had this information years ago! I bought some denim-like fabric that was marked “unknown fabric”. I made a pants and vest combo. I tried it on and as I walked around it gave off a terrible odour! I didn’t smell it when I washed it or when I worked with it. I had to throw it out – I wouldn’t give it to a thrift store in case someone with a poor smell bought it!
Oh, oh, oh – thanks, perfect timing! I was just going through my fabrics, wondering about a few of them.
Ok, this is an awesome post. I have some mystery fabric's and I have been wondering how to go about figuring out what they are made from. Pinning this for sure.
This is very helpful. I get fabric given to me for all sorts of charity projects. I can usually tell by the feel, what it is, but this is great. I posted this to my Pinterest-Fabric board.
http://pinterest.com/thelostapron/fabric/
CSI detective?!