Seam Allowance: A Beginner’s Guide to Sewing Seams

Seam Allowance: A Beginner’s Guide to Sewing Seams

Shubham Anil Jain
Aditya Birla Fashion and Retail Limited
Bangalore, India


Seam allowance is the space between the fabric’s raw edge and the seamline (also known as the seam stitch line). It provides extra fabric to effectively stitch a seam together, enabling the construction of all seams. Seam allowance is present along the majority of the edges of the fabric pieces that make up a clothing item, even though you can’t see it on the front of the garment. You must learn how to identify seam allowance on a sewing pattern, how to transfer the seam allowance marks onto fabric (if required), and how to apply seam allowance to sew seams correctly as a beginner sewer.

seam allowance

Procedure to Decide Seam Allowance Length:
The type of fabric and seam finishing method chosen for the project at hand are the two key factors that determine the length of the seam allowance. It’s crucial to remember that the most typical seam allowance (used on most regular seams) is either 5/8″ or 1/2″ before we go further into what materials work with what seam allowance. Most seams have a seam allowance of 5/8 if you purchase sewing patterns from a retailer that sells professional sewing supplies. It is advised to use a 1/2″ seam allowance when creating your own patterns because it is simpler to work with and measure.

The most popular lengths are 5/8″ and 1/2″, but seam allowance varies based on the fabric’s weight and weave pattern. A shorter seam allowance length of no more than 1/2″ is ideal for fine, lightweight materials. Larger seam allowances are recommended for fabrics with thicker, looser weaves in order to produce a stronger, easier-to-sew finish. You’ll discover that sewing dense, bulky fabrics with a small seam allowance results in less stability for the machine. Additionally, the short fabric surplus doesn’t provide enough space for the seam to be properly cleaned and polished, which prevents the seam from sitting flat once it is finished.

Having said that, if the piece of clothing you are making requires a thick, heavyweight fabric, be sure to add more seam allowance (3/4″ to 1″) along its main structural seams. Once the seam is stitched, you can easily clip the excess if the seam allowance is too lengthy. Contrarily, once the fabric pieces have been cut and the seam has been sewn permanently, more seam allowance cannot be added.

Importance of Seam Allowance:
The industry standard seam allowance for the shoulder, side, and armhole seams is roughly 12 inch when creating your own patterns from scratch. The quantity of seam and hem allowance added influences whether the garment can be stitched properly, though this can also vary according on your design. It will be nearly impossible to sew the clothing if the seam allowance is too narrow. On the other hand, if the seam allowance is too large, bulk will be added, and bulk ruins the appearance of the garment when it is worn.

Woven fabric frays and the seam allowance protect the stitches. The seam allowance is what allows the garment to be fitted to the body. The seam allowance can be stitched wider if the garment is too big, or let out if the garment is too tight. Determining how much seam allowance you will add determines entirely on you. The most important thing to do is to practice to try out different seam allowance measurements and see how they look after they are stitched. When you decide on the correct seam allowance for you, make sure to keep it consistent among all pattern pieces. As a rule, when a seam is enclosed or shaped, like a curved neckline or collar seam, allow for a ¼ inch seam allowance. It is much easier to stitch a narrower seam around a curved seam.

One last thing to keep in mind. When we get further into fabric manipulation, gathers, pleats, tucks, flounces, and so on. In order to achieve these manipulations, we play within the seam allowance. Everything from adding fullness, to knife pleats all get stitched within the ½ inch seam allowance. The seam allowance may be small, but it has significant purpose in the construction of any garment.

Tips Regarding Seam Allowance:

  1. To prevent unintentional modifications to the overall finished product, any significant adjustments to a pattern should be made before it is cut.
  2. The seam allowance does give flexibility for little changes.
  3. To fold the cloth back on itself and reveal the stitched seam, press the open seam allowance using pressing tools.
  4. Before purchasing fabric, check the seam allowance in the patterns.
  5. Commercial patterns that come in different sizes have lines to cut that already have seam allowances included.
  6. With the aid of a sewing gauge, verify the throat plate’s correctness by examining the proper line.
  7. To prevent holes in your cloth, pin into SA.
  8. With fabric sheers wrapped around curving sides, clip into SA to smooth and decrease bulk.
  9. A SA should be added all the way around the design, except any cut-on-fold areas.

The space between the cut raw edge and the line you will be sewing along is known as the seam allowance. It allows for fraying edges and aids in determining the item’s final size and shape. It’s critical to learn how to add seam allowance correctly and sew the proper sized seam because using the incorrect seam allowance could result in your apparel being either too big or too small. By keeping the tolerance, the cloth can fray without compromising the item’s structural integrity. For various causes, seams might need to be snipped or pressed open, and the pattern designer will have taken this into account while making judgements.



You may also like:

  1. Types of Seam Used in Garments Manufacturing
  2. How to Determine Seam Strength in Garment Industries
  3. Procedure of Fabric Seam Slippage Test
  4. Seam Defects | Common Seam Quality Defects in Garments
  5. Scope of Seam Engineering to Increase the Seam Strength by Controlling Different Parameters

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1 thought on “Seam Allowance: A Beginner’s Guide to Sewing Seams”

  1. Thanks Shubham,

    You have shared this with me at the right time, as l am currently working with my students on this topic




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