Sourcing Best Practices: Design & Technical Specification

The single highest-leverage investment in textile sourcing is not factory selection or price negotiation — it is specification quality. A precise technical specification eliminates the most common and most expensive failure mode: the factory interpreting ambiguity in its own favour. Best-practice textile specifications express every parameter numerically with a tolerance ('500 GSM ±5%, verified ISO 3801'), use Pantone TCX references rather than colour names, specify stitch type by ISO code and stitch density in stitches per inch with a range, and include lab test requirements with pass limits as part of the Tech Pack — so the factory knows at specification stage what it will be measured against at final inspection.

Principle 1: Define Everything Numerically

Any specification that can be expressed as a number should be expressed as a number — with a tolerance. 'Heavy-weight denim' is a subjective description. '320 GSM ±5%, 3×1 twill weave, 100% cotton' is a specification.

Principle 2: Specify Fibre Content to ±3% Tolerance

Fibre content declarations on labels must match actual fibre content within ±3%. If your specification says '100% cotton' but the factory uses a 97% cotton / 3% elastane blend for ease of sewing, the product fails its label claim. Specify fibre content percentage ranges that correspond to the actual composition you will accept — not just the idealised target.

Principle 3: Control the Revision Process

Every revision to a specification after factory review has been shared is a new version — and must be documented as such. A version control system for specs prevents the most common sourcing administration error: the factory working to v1.2 while the buyer has issued v1.4.

• Number revisions sequentially: v1.0 (issued for development), v1.1 (after first comment), v2.0 (major revision).
• Include a revision table at the front of every Tech Pack showing what changed and when.
• Require written acknowledgment from the factory (email confirmation) that they have received and will work to the current version.
• Never send spec updates verbally or via messaging apps without a follow-up written confirmation.

Principle 4: Include Lab Test Requirements in the Spec

Lab test requirements belong in the Tech Pack, not in a separate document that may or may not reach the factory. Specify: the tests required, the standard method (ISO/ASTM), the minimum pass level, and whether pre-production (fabric) or pre-shipment (finished product) testing is required.

Principle 5: Use Images for Placement and Construction Details

Written descriptions of placement (e.g. 'chest pocket positioned 3cm from armhole seam') are ambiguous without a diagram. Use dimensioned diagrams for every placement specification: print position, label location, button placement, embroidery centre point. A photograph of the approved sample does not substitute for a dimensioned diagram — photographs distort perspective and are not reproducible at factory level.

For a specification review before factory submission — including tolerance checks, certification gaps and feasibility at the target price — submit your product details in the sourcing RFQ form.