#23 How to Determine Negative Ease on a T-Shirt Pattern

Understanding Ease in Knit Patterns: A Closer Look at the Jenny T-Shirt

When it comes to achieving a great fit, understanding garment balance and ease is essential—especially in knit fabrics.

This week, I’ll walk you through how to assess the balance lines and ease allowances in the Jenny T-Shirt pattern by In-House Patterns, so you can better understand how and why the garment fits the way it does—and how to replicate that fit for your body.

What Is Ease, and Why Does It Matter?

Ease is the difference between your body measurement and the finished garment measurement.

• Positive ease means the garment is larger than your body (for comfort and movement).

• Negative ease means the garment is smaller than your body (relying on fabric stretch to shape to the body).

Since knit fabrics stretch, they can accommodate negative ease—eliminating the need for darts or shaping seams common in woven garments.

Measuring the Jenny Tee

If you're following along with your own Jenny T-Shirt pattern, you'll want to:

• Mark the bust, waist, and hip lines on the pattern

• Refer to the body measurement chart on the In-House Patterns website

• Use a Pattern Measurement Worksheet (available in the Perfect Fit Guide) to calculate the ease at key points

Be sure to measure along the seam lines—not the cutting lines—and double any horizontal measurements (since you’re only measuring half the garment at a time).

What We Found in the Size XL Jenny T-Shirt Pattern

These values create a classic, body-skimming silhouette with:

• A snug fit through the bust to mold over curves and reduce the need for darts

• Looser ease at the waist for comfort

• A close-fitting hip that defines the hemline

• Additional sleeve ease for natural movement

Why This Matters

Understanding where and why ease is added or reduced allows you to:

• Replicate the intended fit on your body

• Customize the pattern to match your preferences

• Avoid unnecessary muslins and trial-and-error

If you prefer a tighter waist or looser hip, you can adjust the ease accordingly—but be mindful of how those changes affect the garment’s overall balance and drag lines.

Want to Go Deeper?

If you’re ready to explore stretch knit drafting and learn how to create a custom-fit T-shirt from your own measurements, I invite you to explore the online course:
The Custom Stretch Knit Bodice Block

You’ll learn how to draft with stretch ratios in mind, create a reliable block, and modify it for multiple styles—all using your body as the foundation.