A Beginner's Guide To Interfacing

What is interfacing? You may have seen it on the list of notions on your pattern, or heard it mentioned in your local fabric shop, but how do you know when to use it and what type - and what it's even for?

Interfacing is a fabric that you apply between the fabric layers in your project to either give it structure or stability, or to thicken and strengthen the fabric.  You can use it in dressmaking - for example in collars, cuffs, and button plackets, or in craft projects - for example, to mke your bags and purses more sturdy.

You generally apply it to areas in a project that are 'stress' areas - either where the fabric is weaker, or where it gets a lot of pulling (ie where your fastenings are located).

There are so many different types of interfacing though - so which one should you use for any given project?

Most patterns will refer to the interfacing you need as either fusible or not, and then by weight: light,medium, heavy.  Some may refer specifically to brands - you may see names such as Vilene, Pellon, Bosal.  Most of these brands will do similar interfacings, and will have equivalent options.

Fusible Interfacing

Fusible interfacing has a heat activated adhesive on one side - you will use your iron to adhere it to your fabric. It works well on most things, although with highly textured fabrics you may find it has trouble staying stuck.  It's also important to remember that the glue will give your project a slight additional stiffness, so this might need taking into account if the fabrics you're working with are very fine, and you want to keep it that way.

To identify if - or which side of your interfacing is fusible, see if you can feel a slight roughness on one side, or hold it up to the light and see if you can see a shine from the glue.

How to apply: first things first, remember that this is glue, so you do not want to get it on your iron or ironing board!  We suggest using a pressing cloth, or ironing from the fabric side of your project.  Use a medium heat, and press, don't glide, to avoid movement and drag.

Sew In Interfacing

Sew in interfacing is just that - you will sew it onto your main fabric.  This can often result in a more natural drape to your project (see note about the glue in fusible above).  Sew in is harder to use, as you'll be working with shifting layers, so in many cases - especially beginner projects - fusible is the way to go until you're more confident in what you're doing.

Next, we're going to talk about how the interfacing is made, and how that will affect your project!

The vast majority of interfacing is made by bonding fibres together to make a kind of strong tissue - similar to the cloths you clean with.  It has no grainline, and you can cut your pattern pieces any which way you like.  This type of interfacing is cheap and cheerful, and will be perfect for many projects.  You will need to watch out for stretching, though.  If stretched, the fibres can pull apart and tear (again, like a tissue) so be careful not to use this on stretch projects.

You can also get bonded interfacing that has a stitch reinforcement running through it that is often used as support in jackets and outerwear, despite being relatively light. (Vilene H410/ Pellon

You may have heard the term 'woven' interfacing, but many people who have been sewing for years have not come across this, so it's easy for it to have passed you by.

Woven interfacing looks like a regular woven cotton fabric.  It's important to remember that as it's woven you should take into account that it has a grainline, so you should cut your pattern pieces on the straight of grain, so they don't twist.  I find wovwen interfacing gives yo a more flexible finish to your project, and adheres to your project in a smoother way (if you've ever had a bubbly effect when you've applied the interfacing, I find this reduces that possibility).  It's good to use on stretch projects where you need to stop an area from stretching because you don't want them to get baggy (ie pocket openings) because the fibres won't pull apart and the fabric is supported.  Woven interfacing is generally more expensive, but in my opinion you get what you pay for - and if the project is worth it, I recommend the splurge. 

Woven Interfacings include Vilene/Vlieseline G700/ G710, Pellon SF101

Knit interfacing - if you need interfacing on a stretch project, this is for you.  As the name implies, it is knitted in constructuon, so will help you maintain the stretchiness of your garment while still adding body.  Knit Interfacings include Vilene H609/ Pellon 180

Weight

Generally, it's  a good idea to try and match the weight of your interfacing to the weight of the fabric you're using.  Lightweight dress fabrics like rayons, viscose &  lawns would need a lightweight interfacing, medium would need slightly heavier, and so on.  this is obviously unless you're looking to ad a greater level of body and/or thickness. You can utilise various weights for your craft projects, again, from adding stability in the areas you're adding your metal hardware, or all over for adding body.  I've even used multiple layers to get the exact weight I'm after, while still maintaining the drape. 

Some craft interfacings are thicker than cardboard, so can be used to makean entirely 3D project - think fabric boxes (Pellon Peltex/ Vilene Decovil).  Add in fusible fleece (Pellon 987F, or Vilene/ Vlieseline H640) and flexfoam (Bosal In-R-Form, Pellon Flex-Foam) for softer structural items.   These heavier weight craft inerfacings can often come fusible on two sides as an option also.

When applying these heavierweight craft interfacings, it's worth removing the seam allowance - so your interfacing is cut on the sew line.  This will reduce bulk in your seams and make it much easier to sew!

This is only a small dive into the world of interfacings, and I hope it's helped a little bit.  I shall add more as things come to me.

Happy sewing! And happy interfacing!!

Anna x