How to write a tech pack a factory understands: structure, examples, free template

A tech pack (technical package, the spec for your product) is the document a factory sews from. Not from a chat thread, not from "same as last time, but with a hood" — but from a sheet that nails down everything: materials, measurements, tolerances, trims, packaging.

The rule is simple and paid for in cash: anything that isn't in the tech pack, the factory will decide for you. Sometimes well. More often not, and you'll have no grounds to argue. You can't attach a verbal agreement to a claim.

Let's walk through the structure of a working tech pack sheet by sheet — in the order a factory's technologist reads it.

Sheet 1. Cover (general info)

The header that lets everyone identify the product at every stage:

• style number and name (for example, KR-FW25-051 / "Loft" Sweatshirt);
• brand, season, category;
• size range (XS–XXL) and the base size the patterns are built from;
• date and tech pack version number — more on this below;
• contact for the person responsible on the brand side;
• key photo or sketch.

Sheet 2. Sketches

A technical drawing (flat sketch) front and back. Not a fashion illustration, but a flat schematic with proportions. Callouts on it mark seam placement, pockets, zippers, prints and embroidery with dimensions and placement coordinates, topstitching. If there's print or embroidery, break out the artwork at actual size as a separate block, with the source file.

Sheet 3. Bill of materials (BOM)

The BOM (bill of materials) is a table of everything the product is made of. The minimum set of columns:

Read the first row the way a factory technologist would. "French terry 3-end, 'Yarn Co.', art. F-320, 320 gsm, color 19-3906 TCX, usage 1.4 m" — there's no room for interpretation here: they buy exactly this fabric, at exactly that weight, in exactly that color. Whereas a row like "terry, grey, ~1.5 m" is an invitation to improvise.

Three typical BOM mistakes:

1. Composition "like the sample" instead of an exact article. On the reorder, the factory buys "something similar," and the weight drifts from 320 to 260 gsm — the product comes out lighter, and the customer writes that "the fabric is thinner than it was."
2. Color in words ("dark grey") instead of a Pantone TCX number. Your "dark grey" and the factory's "dark grey" are two different colors — proven across generations.
3. Forgotten "small stuff": thread, the composition/care label with care symbols, the polybag. These are BOM rows too, otherwise they'll arrive "as available."

Sheet 4. Size chart with tolerances

The heart of the tech pack and the key document in any defect dispute. A table of measurements by point of measure for each size, always with tolerances:

Take the "Body length" row for size M: spec 66 cm, tolerance ± 1.5 cm. That means QC accepts anything from 64.5 to 67.5 cm. Measured 63.5 — defect, and the factory signed up to it by accepting the tech pack. Measured 67 — in spec, nothing to argue about.

Without a tolerance column, the size chart turns into a wish list. With tolerances, it's an acceptance criterion. And one more thing: attach a diagram to every point of measure. "Body length" can be measured three ways — from the shoulder seam, from the neckline down the center back, from the high point of shoulder. Lock in your method with a picture, otherwise the factory picks whichever is convenient for them.

Sheet 5. Construction details and operations

The things you can't see on the sketch: seam types (overlock, flatlock, double topstitch), neckline and hem finishing, stitch length, reinforcement of stress points, label placement down to the centimeter. The more expensive the product, the more detailed this sheet.

Sheet 6. Packaging and tagging

How to fold it, what to pack it in, what to stick on: the individual polybag and its size, a sticker with style number, size, and barcode, the artwork for any factory-applied label with a rule for matching it to sizes, carton packing instructions.

Versioning: where good tech packs go to die

The most destructive mistake isn't in the content, it's in the process. The tech pack was sent, then "the length got tweaked in chat," then again. The factory sews from a file called techpack_final_2_NEW(3).pdf — and guess what length is in there.

Hygiene rules:

• any change is a new version, with a number and date on the cover;
• old versions are clearly marked as void;
• the factory always has exactly one current file, and it's clear where to get it;
• change history is recorded: what changed, who, when.

This is the main argument for keeping tech packs in a system rather than in files: there's one version, it lives online, and the factory always sees the current one. But even in Excel, version discipline saves you from most "they sewed the wrong thing" situations — we collected the common failures in our breakdown of seven spec mistakes.

Where to start

Download our template — an Excel file with ready-made "Cover / BOM / Size chart / Packaging" sheets and pre-configured tolerance columns: the tech pack template generator fills in the cover for your style in a minute.

From PLMflow. In PLMflow, a tech pack isn't a file but a living object: the BOM pulls from the material library, the size chart checks tolerances on its own, the factory sees the current version in its own portal, and change history is written automatically. Try it on your own style →