How to Choose and Apply Fusible Interfacing to Fabric

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Choosing interfacing for your sewing project can be a daunting task. There are SO many options. Sheer, heavyweight, fusible, sew-in, and more!

And for me, at least, picking the right type of interfacing is nowhere near as fun as sewing the actual project.

Applying fusible interfacing can also be confusing to a beginner sewist as well–we’ve all been there and accidentally fused the interfacing to our irons, not fabric.

This interfacing guide will teach you when to use and how to choose interfacing for sewing, how to apply fusible interfacing, and how to attach sew-in interfacing. 

What Is Interfacing and When to Use It

Interfacing is a textile that is applied to the back, or “wrong” side, of fabric to reinforce and give it extra strength and thickness. It also keeps knit fabrics from stretching out of shape.

It plays a supportive role in many types of garments. For instance, the inner layer of collars, waistbands, cuffs, and often buttonholes contain interfacing. Necklines and hems also have interfacing in many cases to add stability.

In addition to providing stability during wear time, interfacing also keeps garments crisp through repeated washings and wearings.

Types of Interfacing In Sewing

There are many different varieties of sewing interfacing, and certain projects may require more than one type of interfacing.

Two main types of interfacing (fusible and non-fusible) are broken down by fiber type. Here’s the breakdown:

• Fusible interfacing (also known as iron-on)
  • Woven fusible
  • Nonwoven fusible
• Non-fusible interfacing (also called sew-in)
  • Woven non-fusible
  • Nonwoven non-fusible

Weights of the interfacing range from sheer to heavy. Also, colors are typically white, black, beige, and gray. Most commonly, you’ll find white or black interfacings at fabric stores.

General Rules for Choosing Interfacing

The biggest rule to remember when choosing interfacing is: do not choose an interfacing weight heavier than the fabric weight. And if you’re not sure what type, choose nonwoven fusible interfacing since it works well on both wovens and knits.

When selecting interfacing, also consider the kind of shaping required for your garment and if the garment is washable.

Choosing between sew-in and fusible interfacing is often based on personal preferences. Fusible interfacing is quick and easy to apply whereas sew-in interfacing requires more work. Some materials cannot handle the high heat required by fusing or cannot be heated because they would lose texture, such as seersucker. These fabrics are better candidates for sew-in interfacing.

Types of Fusible Interfacing (Iron-On)

Now, for a little bit more about fusible interfacing, also known as iron-on interfacing. This type of fusible interfacing has an adhesive backing that’s activated by heat. As I mentioned above, there are two types of fibers for fusible interfacings.

1. Woven

Woven fusible interfacing has a lengthwise and crosswise grain just like woven fabrics do. Designed for use on woven fabrics, make sure the grain of the fabric matches the grain of the interfacing.

Weights range from sheer to heavyweight, which will cover all weights of woven fabrics.

2. Nonwoven

Nonwoven interfacing does not have a grain and does not fray. It’s made by bonding fiber together and is a good, all-purpose interfacing.

Used on both woven or knits, it comes in weights from sheer to heavyweight also. When in doubt, choose nonwoven fusible interfacing in a weight no heavier than your fabric.

Within this category, there are also timesaving interfacing aids such as nonwoven fusible waistbanding to firm up and crisp cuffs and waistbands. This interfacing aid comes in strips and can be precut and premarked with stitching or fold lines.

How to Apply Fusible Interfacing

Always closely follow the directions on the paper insert of your fusible interfacing since instructions can vary. When unwrapping the interfacing from the bolt, this paper insert resides on the back. In addition to how to fuse the interfacing, it provides information about the type of interfacing, its intended use, and care instructions.

In general, though, here are the steps for how to apply fusible interfacing:

1. First, if in doubt, try a small piece of interfacing on a scrap piece of fabric. You don’t want to ruin a whole project if your fabric and fusible interfacing are not compatible!
2. To apply fusible interfacing, use an iron set to the necessary temperature. Check the directions on the interfacing to determine if a dry or steam iron is needed. Most interfacings that I use require a steam iron with a metal plate.
3. Next, place the fabric right side down (wrong side up). Iron it to get out all the wrinkles.
4. Then, lay the interfacing, sticky side (or fusible side) down, on the fabric. If it’s going to slip around, gently pin or clip it on. At this point, I like to go ahead and trim my interfacing to be about 1/4″ – 1/2″ larger than all the fabric.
5. If you pinned, go ahead and gently press a heated iron to the sides of the interfacing to stick it down enough to remove the pins.
6. Then, cover the interfacing with a damp pressing cloth to prevent scorching.
7. Hold the iron firmly on top of the interfacing for 10-15 seconds. Keep the iron on a lower setting to prevent scorching. Heavier fabrics will require a longer pressing time. Try not to move the iron around too much or you may slide the interfacing off the fabric.
8. Once you’ve completed fusing a section of the interfacing, lift the iron, and fuse the next section until you are done. Then, turn the fabric over and steam press the right side of the fabric. (There will be no interfacing on this side.)
9. Let the interfacing cool and lift a small corner to see if it has adhered properly. If so, you have successfully applied your interfacing!

Using Non-Fusible (Sew-in) Interfacing

As with fusible interfacing, non-fusible interfacing is available and comes in either woven or nonwoven. It is also available in several different weights.

When adding it to a project, non-fusible interfacing should first be pinned in place, then basted to the wrong side of the fabric, and then stitched in place with a sewing machine.

In the case of heavyweight sew-in interfacing such as nonwoven sew-in waistbanding (helps stiffen belts and waistbands), you sew it into the facing (or back) of the waistband. It is too stiff to be sewn into a waistband seam.

One Other Type of Interfacing: Fusible Web

There’s also a type of interfacing aid called fusible web that comes in various widths. This can be used to bond sew-in interfacing in the place of pins, as it is made to bond two pieces of fabric together when heated.  It also can be used for making seamless hems and will hold appliques or patches in place before stitching so you don’t need to use pins.

Interfacing vs. Stabilizer

If you’re an embroidery enthusiast, you may already know about stabilizer for embroidery machines.  Used while embroidering or appliqueing, stabilizer reinforces fabric while it’s being stitched.  In contrast to interfacing, stabilizer is mostly removed after stitching is complete.

In conclusion: Now that you’ve learned more than you probably ever wanted to know about choosing and applying interfacing, I hope you boldly march into the fabric store next time and select your interfacing with confidence!