How to Read a Tech Pack: A Guide for Beginners
How to read a tech pack — understanding flat sketches, measurement charts, bill of materials, and construction notes for garment production.
Tech pack structure overview
A tech pack is organized into distinct sections, each communicating different aspects of the garment specification. Understanding how to read each section lets you evaluate tech packs, communicate with manufacturers, and catch errors before they become expensive production mistakes.
Reading flat sketches
Flat sketches show the garment laid flat with construction details annotated. Look for:
- Overall silhouette and proportions
- Seam lines and their construction type (shown with different line styles)
- Topstitching (shown as dashed or dotted lines parallel to seams)
- Pocket placement, size, and construction details
- Closure locations and types
- Detail callouts with leader lines pointing to specific construction points
Reading the measurement chart
The measurement chart lists every point of measure (POM) with values across all sizes. Key things to check:
- Are all necessary points of measure included?
- Do the grade increments make sense (consistent progression between sizes)?
- Are tolerances specified for each measurement?
- Is the measurement method defined (e.g., 'measured flat, 1 inch below armhole')?
- Do the measurements match the intended fit?
Reading the bill of materials
The BOM tells you every material used. Verify that each entry includes a specific description, supplier reference, color code, and quantity. Watch for vague entries like 'cotton fabric' — these should be specific: '180 gsm 100% cotton jersey, Pantone 19-4052'.
Reading construction notes
Construction notes specify how the garment is assembled. Look for stitch type codes (301, 401, 504, 602), stitches per inch, seam allowances, and finishing methods. If you are unfamiliar with stitch type codes, reference the ASTM stitch type classification system.