Riley Blake Triangle-In-A-Square Quilt 4 - Downloadable PDF

Riley Blake Triangle-In-A-Square Quilt 4 – Free Downloadable PDF Pattern by Gerri Robinson

This free downloadable PDF pattern, Triangle-In-A-Square Quilt 4, is designed by Gerri Robinson of Planted Seed Designs™ and produced in partnership with Riley Blake Designs. The finished project is a striking lap or throw quilt measuring 54" x 68", built entirely around the classic Triangle-in-a-Square block construction method. With its bold, colorful geometry and structured assembly, this pattern is an excellent choice for quilters who enjoy specialty ruler techniques and want to showcase a vibrant fabric collection.

What Is Being Made

The finished piece is a 54" x 68" quilt composed of 153 Triangle-in-a-Square (TIAS) units arranged in 17 horizontal rows. The overall design creates a dynamic, repeating geometric pattern that highlights the contrast between a neutral background fabric and nine assorted colorful prints. The quilt is suitable for use as a lap quilt, throw, or decorative bed topper for a child's or guest room.

Techniques Used

• Triangle-in-a-Square (TIAS) block construction – Each of the 153 units is made using one center triangle and one pair of side triangles, following the specific method outlined for the Planted Seed Designs' Triangle-in-a-Square Tool. This specialty ruler is required to complete the pattern accurately.
• Strip cutting – Background and print fabrics are cut into width-of-fabric (WOF) strips before being sub-cut into triangles and rectangles, streamlining the cutting process.
• Row-by-row assembly – The 153 TIAS units and background rectangles are pieced into 17 horizontal rows, which are then sewn together to form the complete quilt top.
• Layering, basting, and quilting – The pattern instructs quilters to layer the quilt top, batting, and backing, then baste and quilt as desired before finishing.
• Binding – The quilt is finished with a traditional strip binding using seven 2-1/2" x width-of-fabric strips.

Stitches and Block Structure

The primary construction relies on straight-stitch piecing on a sewing machine, joining triangular and rectangular fabric pieces to form each Triangle-in-a-Square unit. The TIAS block is a classic quilting block in which a large center triangle is flanked by two side triangles to create a square unit — a technique that, when repeated across a quilt, produces a visually energetic, tessellating pattern. Precision in cutting and sewing is essential, and the Planted Seed Designs' Triangle-in-a-Square Tool is specifically designed to eliminate guesswork and ensure consistent, accurately sized units throughout.

Fabrics and Materials

• Background fabric: 3-1/4 yards of Riley Blake Confetti Cotton in C120-Cloud — a crisp, neutral tone that allows the colorful prints to stand out vividly.
• Block prints: 3/8 yard each of nine assorted prints from the Gem Stones Bright Collection for Riley Blake Designs, including:
  • Print 4: Rainbow Bright
  • Print 6: Blizzard Blue
  • Print 8: Lagoon Blue
  • Print 11: Purple Heart
  • Print 13: Spring Green
  • Print 16: Dreamsicle
  • Print 17: Violets are Blue
  • Print 20: Pretty Flamingo
  • Print 21: Orange Glow
• Binding fabric: 5/8 yard, cut into seven 2-1/2" x WOF strips.
• Backing fabric: 4-1/4 yards.