How to Stretch Out a Knit Hat

Your special someone knits you a hat for Christmas—in your favorite color—but it’s so tight it gives you a headache. Or your best knit hat accidentally goes through the wash and comes out smaller. Can these hats be saved? Is there any way to stretch out a knit hat?

Your chances of stretching out a knit hat to the correct size will depend on several factors:

• Type of yarn (wool, cotton, acrylic, or blend)
• Type of knit pattern (ribbing, cables, Fair Isle)
• Did the hat shrink in a hot wash?

Some yarns and some patterns will allow for more stretching. Others may not stretch much at all.

Stretching Different Kinds of Yarn

Hats can be knit from any kind of yarn. Yarn can be made from natural fibers such as wool, cotton, or silk. Other yarn is made from acrylic (plastic-based) or metallic fibers. There are also blends. Wool tends to be the most resilient fiber, so a wool hat will be usually be easier to stretch out. Acrylic yarn is less resilient, and cotton even less so.

Stretching Different Types of Knitting Patterns

There are thousands of different kinds of hats, but many use similar patterns or techniques. These patterns create different textures in the knitted fabric. Some knitted fabrics will be easier to stretch out than others.

• Ribbing: Ribbing patterns alternate knit and purl stitches to create a corrugated fabric that has a lot of give. Ribbing naturally pulls the knit fabric together, but also allows for some expansion. Ribbing is commonly used in knitting hats, especially around the brim.
• Cables: Many knit hats employ different cable patterns in their design. These cables appear as curved cords that twine together. Cables create a knitted fabric that is pulled together, without much stretch.
• Fair Isle: Fair Isle knitting uses multiple colors to create designs and images. Each color is carried along the back of the knitted fabric, creating a dense fabric that does not have much stretch.

Felted Hats Cannot Be Stretched

Knowing the yarn and type of pattern used in your hat will give you some sense of your odds in successfully stretching it out. Knit fabric can be very forgiving, however, so you might want to take a chance, anyway. That’s fine, unless you want to stretch out a wool hat that got smaller after going through a hot water wash. When wool is agitated in hot water, the fibers in the yarn end up condensing—permanently. The process is referred to as felting. You will notice that your felted hat is not only smaller, but feels much thicker. There is no way to stretch out this hat. Either give it to someone a few head sizes smaller, or use the fabric in a felt project.

Methods for Stretching Out a Knit Hat

Reblocking: Blocking a knit hat refers to the process of soaking the finished hat in mild detergent, rinsing it, and then allowing it to dry in the preferred shape. You can try reblocking a hat that is a bit too small or tight:

• Soak the hat in warm water with mild detergent for 20 minutes. For hats made from wool or wool blends, use a non-alkaline detergent, such as Ivory or Dawn, baby shampoo, or commercial wool soap
• Rinse the hat in warm water
• Put the hat between two towels and press out excess water
• Stretch out damp hat to the size and shape desired
• Let hat dry completely

Reblock using a form: Another way to reblock a hat is to use a form that will give the size you desire. It is possible to purchase human head forms. However, you can also use cider jugs, bowls, pumpkins, pillows, or a head of cabbage, if you find one the right size.

Follow the steps above for soaking, rinsing, and pressing out water. After that:

• Gently stretch damp hat over your form
• If the type of yarn or knit pattern prevents the hat from stretching enough, you can try tugging the fabric in different directions to find some give
• To stretch a beret, choose a plate with the same diameter as your desired finished size
• Allow hat to dry on the form

Not every knit hat can be stretched out, but you may be able to salvage a hat you especially like if it is knit with the right yarn and has a forgiving pattern.