Grecian Square Quilt Block Pattern

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How to Sew the Grecian Square Quilt Block

The Grecian Square quilt block is a beautiful and intricate design that adds a touch of elegance to any quilt.

Materials:

• Fabric in two contrasting colors (one light, one dark)
• Rotary cutter, cutting mat & ruler
• Sewing machine & thread
• Iron and ironing board

Instructions:

1. Cut two 12½" squares of fabric in contrasting colors — these form the base of your block.
2. Place the squares right sides together and sew a ¼" seam along all four edges.
3. Use your rotary cutter and ruler to cut the sewn squares into four 6½" smaller squares. You'll have eight squares total (four of each color).
4. Take one square of each color, place right sides together, and sew a ¼" seam along one side.
5. Open the squares and press the seam allowance toward the darker fabric.
6. Take another light square and place it right sides together with the dark square. Sew a ¼" seam along the opposite side of the dark square.
7. Open and press the seam allowance toward the lighter fabric.
8. Repeat steps 4–7 with the remaining squares to create four half-square triangles total (two of each color).
9. Arrange the four half-square triangles into a square, rotating each so the dark fabric forms a square in the center. Sew together with a ¼" seam allowance.
10. Press seams open or to one side as preferred.
11. Your Grecian Square block is complete! Repeat to create as many blocks as needed, then arrange and sew into a quilt top. Add batting and backing, quilt as desired, and bind the edges.

Making Half-Square Triangles

This technique eliminates the need to directly manipulate the stretchy bias of the triangle. It uses two easy-to-cut squares to produce two half-square triangles.

On the back of the lighter fabric, draw a pencil line diagonally from corner to corner.

Stack a pair of light and dark squares right sides together. Sew a ¼" seam allowance on each side of the line.

You will end up with something like this:

Now cut along the diagonal line.

Press the seam to set it, then press toward the darkest fabric.

To trim to the exact size, line up the 45° diagonal on your ruler with the seam.

Then carefully trim your block with a rotary cutter.

Nine Patch Piecing

The secret to the nine patch is pressing seams so they butt when joined. Cut 5 A squares and 4 B squares in the required size.

Using chain piecing, join a B square to 3 of the A squares, right sides together, with a ¼" seam allowance. The result will be:

Next, chain piece the remaining A and B squares to these units:

Your result will be:

To make this faster, cut A and B strips at the appropriate width and join into A/B/A and B/A/B units. Press every seam toward the dark fabric, then cut across the pre-joined strips:

Same result, but faster:

Press all seams toward the dark fabric so they butt up. Join the B/A/B units to your A/B/A units with butted seams and a ¼" seam allowance. This methodology applies to all kinds of 9-patch blocks — as long as the block has an underlying 3×3 grid, the principle applies.

When it's not obvious which direction is the dark in complicated blocks, remember the basic ironing plan:

How to Resize Quilt Blocks

The first step in modifying any quilt block is to decide on the finished size. You can base this on doubling a pattern, cutting it in half, or working with your available fabric.

Important: Always remove the seam allowance before doubling or tripling the size. For example, if your pattern calls for 3½" squares, subtract the seam allowances (½"), double the finished block size (3" → 6"), then add the seam allowance back (½"). You'll end up cutting a 6½" piece of fabric.

Resizing Square Blocks

Add ½" to your desired finished block measurement. For a 4" finished square, cut a 4½" square of fabric.

Resizing Rectangular Blocks

Add ½" to both the length and width. To double a block that measures 3" × 4", cut a 6½" × 8½" rectangle of fabric.

Resizing Half-Square Triangle Blocks

Add ⅞" to the desired finished block size. For a 4" finished block, cut 4⅞" squares.

Resizing Quarter-Square Triangle Blocks

Add 1¼" to the desired finished block size. For a 4" finished block, cut your squares 5¼".