Riley Blake Triangle-In-A-Square Quilt 5 - Downloadable PDF

Riley Blake Triangle-In-A-Square Quilt 5 by Gerri Robinson – Pattern Summary

About This Free Downloadable Quilt Pattern

This is a free downloadable PDF quilt pattern called Triangle-In-A-Square Quilt 5, designed by Gerri Robinson of Planted Seed Designs in collaboration with Riley Blake Designs. The finished quilt measures a generous 72 inches wide by 76 inches tall, making it a substantial lap or bed quilt suitable for confident beginner and intermediate quilters who want to explore a striking geometric block construction.

What Is Being Made

The project is a full-size patchwork quilt built entirely around the Triangle-in-a-Square (TIAS) block. This classic quilting unit places a center triangle flanked by two side triangles to create a sharp, dynamic arrow or chevron-like shape within a square frame. When repeated across seven vertical rows and combined with plain background squares and small rectangles, the design produces a bold, rhythmic visual pattern with strong directional movement. The quilt is assembled in vertical rows before the rows are sewn together, a construction method that helps keep bias edges aligned and the layout manageable.

Special Tool Required

A key requirement of this pattern is the Planted Seed Designs Triangle-in-a-Square Tool, a specialty quilting ruler designed specifically to cut accurate center triangles and matching side triangle pairs. This tool eliminates the guesswork involved in cutting bias-edged triangles and ensures that every TIAS unit finishes to a consistent size. Quilters who do not already own this ruler will need to acquire it before beginning the project, as the cutting and construction instructions in the pattern are written specifically around its use.

Techniques Used

• Triangle-in-a-Square unit construction – assembling 228 individual TIAS units, each made from one center triangle and one pair of side triangles
• Specialty ruler cutting – using the Planted Seed Designs Triangle-in-a-Square Tool for precise triangle cutting
• Strip cutting – cutting width-of-fabric (WOF) strips and sub-cutting them into triangles, squares, and rectangles
• Vertical row assembly – piecing seven vertical rows before joining them to complete the quilt top
• Layering, basting, and quilting – standard quilt finishing steps to sandwich the top, batting, and backing
• Binding – finishing the quilt edges with straight-grain binding strips

Stitches and Piecing Methods

This is a machine-pieced quilt pattern using standard straight-stitch sewing throughout. All seams are sewn with a consistent quarter-inch seam allowance, which is the foundation of accurate quilt block construction. The triangle units involve sewing bias-cut edges, so careful pressing and handling are important to prevent stretching. The specialty ruler helps mitigate this challenge by standardizing the cut shapes before sewing begins.

Fabric and Materials

The pattern was designed using specific Riley Blake Designs fabric collections, and the materials list reflects those exact choices, though quilters may substitute fabrics of similar value and scale.

• Background fabric: 4½ yards of Riley Blake Confetti Cotton in C120-Cloud, a crisp neutral used for the 228 pairs of side triangles, 72 background squares measuring 4½ inches, and 85 rectangles measuring 2½ by 4½ inches
• Block center triangles – four assorted Gem Stones prints: ½ yard each of Raspberry Dazzle (Print 2), Blizzard Blue (Print 6), Dreamsicle (Print 16), and Orange Glow (Print 21) from the Gem Stones Bright Collection, each yielding approximately 38–40 center triangles cut from 4½-inch WOF strips
• Gem Stones Sonic Green (Print 27): 5/8 yard, providing 54 center triangles cut from four WOF strips
• Gem Stones Purple Heart (Print 11): 3/8 yard, providing 20 center triangles cut