How to Write Garment Specifications for Manufacturing
How to write clear garment specifications for manufacturing — covering measurements, construction notes, materials, and quality requirements.
Why specification clarity matters
Every unclear specification in your garment documentation is a potential production error. Manufacturers interpret ambiguous instructions based on their defaults, which may not match your intent. Clear, precise specifications protect your design vision and save money on sample revisions.
Good specifications are measured, not described. 'Medium weight' means different things to different people. '240 gsm' is unambiguous.
Writing measurement specifications
Measurements are the foundation of garment specs. For each point of measure, include the measurement value, the tolerance (acceptable deviation), and the measurement method.
- Always specify the unit (inches or centimeters) and stick to one system
- Include tolerances: typically ±0.5 inch for body measurements, ±0.25 inch for details
- Define measurement points precisely: 'chest width measured 1 inch below armhole seam, laid flat'
- Grade consistently across sizes — typically 1-2 inches between sizes for tops
- Include critical fit measurements: body length from HPS, chest width, shoulder width, sleeve length
Writing construction specifications
Construction specs tell the manufacturer how to assemble the garment. Be specific about:
- Stitch types: 301 lockstitch, 401 chainstitch, 504 overlock, 602 coverstitch
- Stitches per inch (SPI): typically 8-12 SPI depending on application
- Seam allowances: specify in fractions of an inch (3/8", 1/2", 5/8")
- Seam finishes: serged, bound, flat-felled, French seam
- Topstitch details: distance from edge, single or double needle
- Bartacking: locations and size for stress points
Writing material specifications
For each material in your BOM, include:
- Fiber content: '100% combed ring-spun cotton'
- Weight: '240 gsm'
- Construction: 'French terry, 3-end fleece'
- Width: '60 inches'
- Finish: 'enzyme-washed, brushed interior'
- Color: 'Pantone 19-4052 TCX Classic Blue' or supplier reference
- Supplier: Name and reference number if applicable