What is the Best Way to Block Knitting? (Step-by-Step)

Article by Emma Lane

Knitting projects don’t reveal their full beauty without blocking. Once you bind a project off your needles, there will still be uneven tension and other irregularities. And if you’ve made knitted lace, especially with a very light yarn weight, it might look closer to something the cat threw up than the lovely lacework you envisioned. But how to block knitting?

How to Block Knitting Index

how to block knitting

What is Blocking and Why Should You Do It?

Blocking is a process where you use water or steam, and sometimes a bit of reshaping, to even out a knitted fabric.

Because knitting projects are worked over several days, weeks or months, the tension at which they are knit changes. Some days you might be more tired, other days you might be stressed. It can all take a toll on your knitting, especially when you’re just learning how to knit. Blocking knitting helps even out stitches so that they look like they were knit at the same tension.

Then there are some stitch patterns, such as lace, that need water or steam, and a bit of stretching (okay, sometimes a lot of stretching) in order for the pattern to show up. Blocking is also necessary for lace fabrics to match the final dimensions of a project.

Blocking knitting can also help to solve some size problems, particularly with sweaters. If a piece is too small, it can be stretched during blocking. If they are different sizes (such as the front is longer than the back), blocking can be used to stretch the smaller piece so that it matches the larger.

What Types of Knits Should be Blocked?

Yarn is the key element in everything you knit. Just as you had to consider what kind of yarn to use for your knitted project, you also have to consider your yarn when blocking.

While most yarns can be blocked, there are some that you should knot block. Do not block anything made with metallic or novelty (heavily textured) yarns.

If your knits are lumpy or bumpy, unevenly knitted, or the pattern doesn’t show up well, blocking can make a world of difference!

You should always block your swatch first so that you know whether the fabric will stretch or shrink. For example, cotton usually shrinks while alpaca normally stretches. If you’re making a garment where size matters, such as a sweater, it’s best to find out before you start knitting so that you can correct the size accordingly, or you might find all of your hard work and countless hours has created something too big or too small to wear.

If you’re unsure how your yarn will react to heat and water, blocking your swatch is a great way to test the fiber. It isn’t fun to watch a project turn out differently than you planned because you didn’t test the swatch first.

Blocking Different Fibers

Different fibers react differently to heat and water. Check what kind of fiber you used before you try one of the blocking methods below.

If your yarn is a mixture of different fibers, you should generally follow the blocking method for the predominant fiber. However, If there is any synthetic fiber in the yarn, only use the appropriate blocking methods for the synthetic fiber (usually mist blocking).

I go into more detail below, but I’ve created a quick infographic to help you know how to block different types of knits:

how to block knitting projects by fiber

One of the easiest ways to know how to block knitting is to read the label. Most yarns can be washed, even if the label says “dry clean only.” Dry cleaning is usually recommended for yarns that will shrink significantly or will lose a lot of dye when wet.

Washing and blocking your swatch will let you know how a “dry clean only” yarn will react to washing. If the results of blocking your swatch indicate that it shouldn’t be washed, you can always try blocking your garment with the mist method (see below).

Metallic and novelty yarns typically aren’t blocked. Heat can cause metallic yarns to melt; water can cause some to rust. Novelty yarns can lose their texture in blocking. If you think a fabric made from these yarns needs to be blocked, always test your swatch first.


  1. Irons and Steamers – You don’t need anything fancy or expensive, but it needs to be able to emit a strong shot of steam.
  2. T-Pins – While you can technically use any type of rustproof pin, even straight pins, T-pins are strong and unlikely to bend when stretching fabrics tightly. The broad T-shaped end helps to hold fabrics without the pin slipping through them. This is especially useful when blocking lace.
  3. Blocking Wires – I love blocking wires. They truly simplify the blocking process and give a straighter edge than pins alone. They’re great for everything from scarves and shawls to sweater pieces. To use them, you slip the wires through the stitches at the edge of the fabric and stretch it to your desired dimensions, using a few T-pins to hold it in place on your blocking surface.
  4. Sock and Glove Blockers – As the name implies, they’re forms for blocking socks and gloves. You simply insert them into the sock or glove. I’ve never found much of a need for them, as I prefer to block gloves and socks with pins and wires.
  5. Wool Wash – It’s a specially formatted soap for washing wool when wet blocking. Gentle shampoo works just as well. Make sure you rinse your fabric well before blocking.
  6. Blocking Mats – Mats provide a large flat surface that you can stick pins into. You can buy blocking mats marked with a grid to help you measure. Anything soft enough to hold the pins and that doesn’t absorb water will work. I’ve always used interlocking foam squares and lay grid interfacing with 1-inch squares printed on it on top.

How to Block Your Knitting

What is the best way to block knitting? Right side up so that you can see how what you’re doing is affecting your knitted fabric.

Make sure to give blocking as much attention, time and care as you gave your fabric while knitting it.

There are three blocking methods. The method you use will depend on the fiber the fabric is made with and what you’re looking to accomplish by blocking.

How to Wet Block

Best for: wool, cashmere, alpaca, quiviut, mink, camel, cotton, and linen

Wet blocking allows you to make the biggest difference in fabric – in terms of both size, tension and behavior. It must be done gently by hand. Wool and other animal fibers can become felt if they are agitated too much. You’ll need about an hour’s time to wet block your garment.

What You’ll Need

  • A sink or basin
  • T-Pins
  • Blocking wires
  • Blocking mats
  • A large, thick towel
  • The project’s schematic
  • Wool wash (optional)


  1. Fill the sink or basin with enough lukewarm water to cover the knitted fabric.
  2. If the fabric needs to be cleaned, add wool wash. Swirl the water around enough to mix the soap in, but not to the point that it becomes foamy or it will be difficult to rinse out.
  3. Put the fabric in the water, gently pressing down to help it absorb the water.
  4. Leave it to soak for 20-30 minutes.
  5. Empty the water out, and gently press the water against the side of the sink or basin. Lift it, with the entire project int your hands so it doesn’t stretch, and gently squeeze the water out with a very light pressure – don’t wring it or twist it forcibly.
  6. If you used wool wash, refill the sink or basin with lukewarm water. Gently squeeze the fabric a few times to rinse out the soap. Empty the water again, and gently press out the water. Repeat this step until you’ve remove all of the soap.
  7. Lay the knitting out flat on the towel. Roll the towel up (with the knitting in it), and firmly squeeze out as much water as you can. If the towel becomes saturated, repeat with another dry towel.
  8. Unroll the knitting from the towel, and support it fully as you place it on your blocking mats. Shape the fabric to match the size and dimensions of the schematic, stretching or pinching up anything you would like to emphasize (such as stretching for lace and pinching up for cables). Use blocking wires and T-pins to hold it in the correct shape and size.
  9. If there are any decorative edges, you can pull out points and scallops to emphasize them, using blocking wires and T-pins to hold them in place.
  10. Leave the fabric pinned until it is completely dry. I usually leave it for 24 hours to be on the safe side.
  11. Gently remove the pins.

How to Steam Block

Best for: wool, cashmere, alpaca, quiviut, mink, camel, cotton, and linen

Steam blocking is useful for when your fabric doesn’t need a lot of stretching or you only need to block a few areas of a garment, such as the collar.

What You’ll Need

  • An iron or steamer
  • A sturdy, heat resistant surface, such as an ironing board, table, countertop or dressmaker’s form
  • Project schematic
  • Blocking wires (optional)
  • T-pins (optional)
  • Towel (optional)


  1. If your surface isn’t covered with fabric, lay the fabric or towel on top of it to protect it from the iron or steamer.
  2. Lay your knitted fabric on top, roughly shaping it to the size of the schematic. Pin it in place if needed with the wires and T-pins.
  3. Hold the iron or steamer an inch or so above the knitted fabric and shoot steam at it. (Do not touch the fabric with the iron or steamer.)
  4. Flatten and shape the knitted fabric gently with your hands – pinch cables, stretch open lace work or eyelets.
  5. Allow the knitting to dry completely before gently removing any wires and T-pins.

How to Mist Block

Best for: angora, mohair, wool blends, silk, bamboo, tencel, and synthetic fibers such as acrylic and nylon (always check the label first before blocking synthetic fibers – or your swatch if you’ve lost the label)

Mist works best when your knitting doesn’t need a lot of stretching or when your yarn was a delicate fiber.

What You’ll Need

  • A spray bottle filled with cool water
  • Project schematic
  • Blocking wires
  • T-pins
  • Blocking mat


  1. Using wires and T-pins, pin the knitting on your blocking mat, according to the project schematic.
  2. Use the spray bottle to mist the knitted fabric surface until it feels most. (Note: the underside of the fabric should be damp).
  3. Allow the knitting to remain in place until it is completely dry.
  4. Gently remove the wires and T-pins.

Tips for Hats and Sweaters

Hats and sweaters require some special blocking tricks. Nothing complicated, just a few minor adjustments to get the right fit.

How to Block a Hat

When you block a hat, you replace blocking mats with a plate. You need to use a plate that is similar to the final dimensions you want the hat to have. If the plate is too big, it can stretch the hat so that it is too big and the ribbing is too loose to wear easily. If the plate is too small, the pattern detail may not appear as well as you would like.

Blocking a hat is as simple as inserting the plate into the hat after the fabric is wet. Leave the plate in the hat until the fabric is completely dry.

If you want a more rounded shape, you could try a bowl or a mannequin head in place of the plate.

How to Block a Sweater

It’s best to block sweater pieces before assembling. This not allows you to make sure the pieces are the right size before you sew them together, but it will be easier to sew them because the pieces will curl less and any corners or curves will be neat.

After you lay out your wet sweater pieces, you’ll need to use a tape measurer and your sweater’s schematic to match the pieces to your desired size. Check the dimensions of the shoulders, armholes, neckline and other areas against the schematic, adjusting to match as needed.

You can make minor adjustments to width and length, but with most fabrics, lengthening a piece can cause some loss in width, and widening a piece can cause some loss in length. You usually can’t lengthen and widen at the same time.

After you finish seaming your sweater, you may want to block it again if seams need to be flattened, or if corners or collars need a bit of shaping. Sometimes you might only need a bit of steam for seams, corners and collars.

DIY Mats

It’s easy to make your own blocking mats for knitting.

You need something that is soft enough to insert pins into. Rubber floor mats and foam floor tiles (like you often see in children’s play areas) work well. If you use children’s interlocking foam mats, make sure you don’t get the kind with removable numbers and letters. I know from personal experience that these can be fussy for blocking because the letters and numbers fall out too easily. Something solid is best.

Make sure that your mat won’t absorb water. If it isn’t water resistant, you’ll need to cover it with a protective barrier, such as a plastic trash bag, contact paper or oilcloth.

Next you need to cover your mats with material to create a gridded guide. Things that work well include 1-inch squared interfacing and 1-inch checked gingham. You’re going to be sticking pins in it and putting wet fabric on it – it needs to be durable, but it doesn’t have to be expensive. Whatever you choose, make sure it isn’t made with a dye that runs when wet or your knitted garments will quickly become discolored when you block them.

I’ve used 1-inch squared interfacing and interlocking foam mats for years with no issues. They’ve held up well and pins haven’t made them too “holey” for use. I can see my homemade blocking mats lasting for many more years to come.


Blocking gives your knitted projects a polished, finished look. But if it isn’t done correctly, it can ruin all of your hard work knitting. Make sure you select the right method for the yarn. Don’t throw anything into the washing machine unless the yarn label specifically says it’s okay. Be patient and take your time. In the end, you’ll be rewarded with a finished garment you’re proud of – and an appreciation for how you can transform handmade knitted projects with blocking. Before you know it, you’ll be teaching others how to block knitting.

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