Today, I’m going to share some sewing tips and tricks to avoid disasters and phrases like: "Help, my fabric shrank!" or "Help, I don’t have enough fabric for my project!"

I regularly receive questions from customers or students about washing, how much fabric to buy, etc. I thought a little summary article would help prevent many disasters for both beginners and more experienced sewers.

Note that this article is aimed at hobbyist sewers, and in the fashion industry and professional garment making, other techniques may be used.

So, let’s get started!

What information is necessary before washing your fabric? 

The first question to ask when buying fabric is its composition.

Knowing the material of your fabric piece will help you determine if you can machine wash it and, if so, at what temperature or washing program. The best way to do this is to refer to the manufacturer’s care instructions detailed on the product sheet.

In our online shop, you will find the type of composition and the manufacturer’s care advice in the description of each product.

Is it really necessary to wash your fabric before sewing it?

Yes, yes, and yes! Let’s look at the reasons together.

The first and most important reason for washing is the potential shrinkage of the fabric during the first wash. Indeed, natural fibers tend to tighten during the first wash. It is therefore important to wash your fabric, or else you might not be able to fit into the garment you carefully made...

The second reason is to remove the finish that the manufacturer applied to the fabric to enhance it. This finish stabilizes the fabric, gives it color, shine... It’s important to remove this finish layer before working with the fabric. This will also allow you to assess its true drape and whether this is the fluidity you want for your garment/confection.

The third reason is that your fabric may bleed, meaning the dye may run. Indeed, the fibers are saturated with pigments that will dissolve in the wash water. Blue, black, and red fabrics are the most likely to bleed. Who hasn’t had blue hands after handling a new pair of jeans? You can help set the color a bit more with this old trick: soak your fabric piece for about 1 hour in a bucket of cold water with 200ml of white vinegar (make sure to mix the water and vinegar well before submerging the fabric). After this bath, wash your fabric according to the recommendations.

Finally, the fourth reason: washing cleans the fabric and removes dust, microorganisms, etc., that it may have encountered during manufacturing, transport, storage...

If it shrinks... What information is useful to properly choose the amount of fabric?

Two scenarios arise here: either you work with a pattern from a designer, or you create your own pattern from a tutorial, etc...

1. I buy a pattern

When you buy a pattern, the designer will indicate a fabric length based on your size for making the model.

Designers take into account the average shrinkage percentage of garments (with an average coefficient) and usually add a safety margin. That’s why sometimes you end up with 20 or 30 cm of unused fabric... Some of you might complain about having scraps... but personally, I prefer to reuse my scraps in another project rather than run out of fabric to cut all my pieces... don’t you?

2. I create my pattern

When you create a pattern from a tutorial, most of the time the person will give you finished piece dimensions, meaning fabric already washed (sometimes seam allowances not included)... this is where most mistakes happen... trust me 😊

For example, if you want to make a baby blanket of 1m by 1m, you need to take into account the shrinkage factor of the chosen material, or else your blanket won’t be 1m but rather 90cm.

The same goes for skirts: if you follow a tutorial that tells you to take a rectangle 60cm long, add at least 10cm when buying to be sure that once the fabric is washed, you will have the requested rectangle; otherwise, you might end up with a mini skirt!

Knowing the average shrinkage factor is a prerequisite for this kind of project!

Average shrinkage rate depending on fiber type

Each fiber has an average shrinkage rate depending on the quality of the weave, finishes... I tried to compile the average shrinkage rates by fiber type.

General fabric shrinkage rates:
- Cotton (calico): 4% - 10%
- Cotton double gauze: 5% to 10%
- Synthetic fiber: 4% - 8%
- Cotton-polyester blend: 3.5% - 5.5%
- Cotton poplin: 3% - 4.5%
- Cotton twill: 4%

If you only remember one number, take 10% shrinkage as a safety margin.

So, if you need 1m of fabric after washing and you choose cotton calico, ideally take 10% more. That’s 1.1m.

Grab a calculator if needed --> 
[desired length] x (1 + shrinkage rate as a decimal) = length to buy.
Note: don’t forget the parentheses and the percent sign for the shrinkage rate!

In our example above:
1m x (1 + 10%) = 1.1m

With this information in mind, it’s really easy to manage the fabric lengths needed for your projects. Don’t forget your haberdasher is also here to help you 😊.

So, all that’s left is to get started!

Grab your needles!