Search

Quilt Blocks

How to Make Half Square Triangles: Essential Building Blocks of Quilting

half square triangles in multiple formations

** This post may contain affiliate links.  What does this mean?  It means that if you click on one of my links and make a purchase, I will earn a small commission or fee, at no extra cost to you.  For further information, please read my full Policies page. **

WHEN STARTING YOUR QUILTING JOURNEY, IT HELPS TO START WITH THE BASICS.  JOIN ME  FOR A QUICK TUTORIAL ON A FOUNDATIONAL BUILDING BLOCK, THE HALF SQUARE TRIANGLE.

A fundamental block that serves as the building block for countless quilt designs is the Half Square Triangle (HST). In this tutorial, we will take a look at two easy ways to make HSTs. 

Understanding their construction, exploring different techniques, and unleashing your creativity to design stunning quilts are key to enjoying your quilting!

 

 

What is a Half Square Triangle?

Half Square Triangles, or HSTs, are square quilt blocks made by cutting a square in half diagonally to create two right-angled triangles. When these triangles are sewn together, they form a square block with a diagonal seam running through the center. HSTs are very versatile and can be used in various quilt designs, making them an essential skill for quilters of all levels.

To achieve accurate HSTs regardless of the sizes required, precise cutting and measuring are crucial. Use a rotary cutter, ruler, and cutting mat to cut squares to the required size, ensuring clean edges and proper alignment.

 

Fabric Selection and Supplies

The choice of fabrics for HSTs can significantly impact the overall look of your quilt. I prefer to use contrasting fabrics, such as light and dark colours, because this really accentuates the triangular design.  In my Simply Charming Pinwheels Table Top Quilt pattern, you can see how the use of a light and dark colour pairing creates a fun pattern and allows the HSTs to really stand out.

 

 

Next, make sure you have the essential quilting tools. Here is a list of what I like to have on hand when making any quilting project:

Investing in quality tools will help you cut your fabric squares accurately and save you a lot of frustration in the process.

 

Watch my simple tutorial for Half Square Triangle on my YouTube Channel!  Be sure to subscribe and turn on your notifications so you don’t miss out!

 

 

Continue reading below for step-by-step instructions.

 

Traditional Half Square Triangle Techniques

There are several methods to create HSTs, but let’s focus on two fundamental techniques.

Method 1: Sewing on the Diagonal

Using this method, you will start with two squares of fabric, generally one light and one dark, as mentioned above.  Use the following instructions to create two (2) HSTs.

  • Place the two squares right sides together.
  • Draw a diagonal line from corner to corner on the back of one square.

 

fabric square marked diagonally
Start with one line marked diagonally across the fabric. Stitch a ¼-inch seam on each side of the drawn line.

 

  • Sew a ¼-inch seam on each side of the drawn line.
  • Cut along the drawn line to separate the HSTs.
  • Press the seams open or to one side and trim the corners.
  • Square up the HSTs to the desired size.

 

cutting half square triangles
After sewing on each side of the drawn line, cut along the same line. This will result in two half square triangles.

 

Method 2: 8-at-a-time Technique

Using this method, you will start with two larger squares of fabric, again with one light and one dark, as mentioned above.  Use the following instructions to create eight (8) HSTs.

  • Place the two squares right sides together.
  • Mark two diagonal lines from corner to corner, creating an X.

 

10-inch fabric squares marked diagonally
Start by marking one piece of fabric diagonally like an X. Stitch a ¼-inch seam on each side of the marked lines.

 

  • Sew a ¼-inch seam on each side of the two drawn lines.
  • Cut along both diagonal lines (like an X) and then cut across the middle of the square vertically and then horizontally (like a +) to create eight HSTs.

 

fabric squares cut diagonally and across the centre to create 8 half square triangles
By cutting diagonally (like an X) and across the centre (like a +), you wind up with 8 HSTs.

 

  • Press the seams open or to one side and trim the corners.
  • Square up the HSTs to the desired size.

While both methods are accurate, Method 1 is more straightforward.  Method 2, the 8-at-a-time technique, can save time when making multiple HSTs with the same fabric combination.

 

Common Variations and Designs

HSTs can be combined with other quilt blocks to create a wide range of designs.  Experiment with different layouts, colour arrangements, and block placements to create unique patterns.

HSTs are often used to form pinwheels, chevrons, and star designs, adding movement and visual interest to your quilts.

 

Project Ideas with Half Square Triangles

To put your newfound HST skills to use, here are some quick and easy project ideas, perfect for beginners and seasoned stitchers alike:

  1. A simple HST baby quilt with alternating light and dark triangles.
  2. A table runner with HST borders framing a solid center.
  3. Cushions or pillow covers featuring HSTs in a striking design.

 

 

Half-Square Triangles are an essential element in quilting, offering endless possibilities for creating captivating designs. By mastering the construction techniques and exploring various arrangements, you’ll embark on a journey of creativity and self-expression through the art of quilting. Remember to practice, experiment, and have fun as you create beautiful quilts using HSTs!

 


 

Want to remember this?  Save “How to Make Half Square Triangles: Essential Building Blocks of Quilting” to your favourite Pinterest boards!

 

half square triangles in pinwheel layout

 

Related Posts

Hi! I'm Tanya

I’m so glad you’re here!  Let’s get started on creating YOUR Little Handmade Home!

GET INSPIRED!
Search
YOU MIGHT LIKE
Purchase your LIVING WELL PLANNER
QUILTING + SEWING
Shop Fabric at Fat Quarter Shop
300 X 250 banner
Shop ElectricQuilt.com
JOANN Stores
My FAVOURITE Things
Free Shipping for orders over $30