SeeMyQuiltHalf-Square Triangle Diamond quilt block
Sixteen half-square triangles turned so they form rings of diamonds around the center, like a small barn raising setting. Also called Concentric Diamonds.
Cutting chart by block size
6" Half-Square Triangle Diamond (cut for one block)
| Fabric | Cut | Size | Then |
|---|---|---|---|
| Main | 8 squares | 2 3/8" × 2 3/8" | 16 triangles (cut once on the diagonal) |
| Background | 8 squares | 2 3/8" × 2 3/8" | 16 triangles (cut once on the diagonal) |
8" Half-Square Triangle Diamond (cut for one block)
| Fabric | Cut | Size | Then |
|---|---|---|---|
| Main | 8 squares | 2 7/8" × 2 7/8" | 16 triangles (cut once on the diagonal) |
| Background | 8 squares | 2 7/8" × 2 7/8" | 16 triangles (cut once on the diagonal) |
10" Half-Square Triangle Diamond (cut for one block)
| Fabric | Cut | Size | Then |
|---|---|---|---|
| Main | 8 squares | 3 3/8" × 3 3/8" | 16 triangles (cut once on the diagonal) |
| Background | 8 squares | 3 3/8" × 3 3/8" | 16 triangles (cut once on the diagonal) |
12" Half-Square Triangle Diamond (cut for one block)
| Fabric | Cut | Size | Then |
|---|---|---|---|
| Main | 8 squares | 3 7/8" × 3 7/8" | 16 triangles (cut once on the diagonal) |
| Background | 8 squares | 3 7/8" × 3 7/8" | 16 triangles (cut once on the diagonal) |
How to make a 12" Half-Square Triangle Diamond block
- Cut the pieces in the chart above. All measurements include a 1/4" seam allowance.
- Cut the squares marked "cut once" in half on the diagonal. Each gives two triangles. Sew them to their neighbours along the long edge first and press toward the darker fabric.
- Lay all the pieces out as in the diagram. The block is a 4 × 4 grid, and each cell finishes at 3". Sew neighbouring pieces into sections, then the sections into rows, pressing seams in opposite directions from row to row.
- Join the rows. The block should measure 12 1/2" now and 12" once it is sewn into the quilt.
Yardage for a Half-Square Triangle Diamond quilt (12" blocks)
| Quilt size | Blocks | Finished size | Main | Background | Border & binding | Backing |
|---|---|---|---|---|---|---|
| Baby | 3 × 4 (12) | 42" × 54" | 1 1/4 yd | 1 1/4 yd | 1 yd | 3 1/2 yd |
| Lap | 4 × 5 (20) | 54" × 66" | 2 yd | 2 yd | 1 1/8 yd | 4 1/4 yd |
| Throw | 5 × 6 (30) | 66" × 78" | 2 7/8 yd | 2 7/8 yd | 1 3/8 yd | 5 yd |
| Twin | 6 × 8 (48) | 78" × 102" | 4 5/8 yd | 4 5/8 yd | 1 3/4 yd | 9 1/4 yd |
| Queen | 8 × 8 (64) | 102" × 102" | 6 1/4 yd | 6 1/4 yd | 1 7/8 yd | 9 1/4 yd |
| King | 9 × 9 (81) | 114" × 114" | 7 3/4 yd | 7 3/4 yd | 2 1/8 yd | 10 1/4 yd |
Blocks side by side with a 3" border, 2 1/2" binding, 42" usable width and 10% extra.
Four ways to set it
A throw quilt of 12" Half-Square Triangle Diamond blocks in each setting.
| Setting | Blocks | Finished size | Extra fabric |
|---|---|---|---|
| Side by side | 30 | 66" × 78" | – |
| With sashing | 20 | 60" × 74" | Sashing 7/8 yd, Cornerstones 1/8 yd |
| Alternating plain blocks | 15 pieced + 15 plain | 66" × 78" | Plain blocks 2 yd |
| On point | 18 | 57" × 74" | Setting triangles 1 1/2 yd |
See Half-Square Triangle Diamond in your own fabrics
1. Your fabrics (tap a fabric, then choose a sample or your own photo)
2. Block
3. Quilt size
4. Block size
5. Setting
What to buy
| Fabric | Yardage | Cut |
|---|
Based on 42" usable fabric width, 1/4" seams and 10% extra. Your photos stay on your device.
Questions
How many fabrics does a Half-Square Triangle Diamond block need?
Two: main and background. Choose a main fabric that contrasts clearly with the background so the design reads from a distance.
What size pieces do I cut for a 12 inch Half-Square Triangle Diamond?
8 main squares at 3 7/8" × 3 7/8"; 8 background squares at 3 7/8" × 3 7/8".
How many Half-Square Triangle Diamond blocks for a lap quilt?
20 blocks at 12", set 4 by 5 with a 3" border, make a 54" × 66" quilt.
More pinwheels & triangles blocks
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