What's in a tech pack

Documents · Specifications

The document a factory builds and quotes from, section by section — and what goes wrong when a section is missing.

What a tech pack is for

A tech pack is the specification a factory builds your product from. It has to be precise enough that two factories on different continents would build the same thing. They have never spoken to each other, or to you.

It is not a mood board, and it is not a sketch with some notes. It is closer to an engineering drawing than to anything in the design half of the business. Whatever you leave out does not go away. It gets decided by someone in a sample room who has never seen the product you have in mind.

Who writes it, and when

At a brand of any size, a technical designer writes it: the person who sits between design and production and turns a drawing into numbers. At a small brand the founder usually writes it themselves. A freelance technical designer for the first few styles tends to repay the cost quickly.

It is issued before costing, not after. Factories quote from the tech pack — the materials, the construction and the size range are what they are pricing. This is the whole reason it comes first. Two factories quoting from the same tech pack are quoting for the same product, so their prices can be compared. Two factories quoting from a sketch are quoting for two different products.

In pimbo this is gate G2, "Tech pack released". Sourcing stays shut until it passes, so a supplier is never chosen before there's something to quote against.

The seven sections

A complete tech pack has seven parts. Different people read each one: costing, pattern making, the sample room, sourcing and QC. That is why each needs to stand on its own.

Cover and style header. Style name and number, season, the colourways, and the version number. The version number is the least interesting line on the page and the one that stops last month's specification being sewn.
Technical flats. Front, back and side, drawn flat and to proportion, with a label pointing at every seam, pocket and closure.
Bill of materials. Every fabric, trim and component: composition, weight, colour reference, supplier and quantity. "Button" is not a specification; a named button with a supplier code is.
Measurements and grading. Every point of measure with a target for the base size and a tolerance either side, plus the rules that scale it across the size run.
Construction notes. Seam types, stitch density, thread, and how edges are finished. Two garments with identical measurements can wear entirely differently because of this page.
Cost sheet. Materials, labour and the target price. It is part of the pack because it is what the factory prices against.
Revision log. Every change, dated and numbered, with who approved it.

What goes wrong when a section is thin

Factories report the same handful of failures, and each traces back to a specific gap rather than to carelessness.

No tolerances — every sample comes back technically correct and none of them fit, because "about 52cm" was read five different ways.
No grading rules — the product fits in the middle of the range and nowhere near the ends, and you find out at size set.
A vague bill of materials — the wrong zip arrives, and it arrives in bulk.
No colour references — colour is approved by eye, over email, against a screen, and bulk fails to match.
No construction notes — the garment is assembled the way that factory usually assembles that garment.
No revision log — two versions are in circulation and the sample room has the older one.

Each of these costs a sampling round. A round is typically weeks, and weeks come out of the critical path — which is why an incomplete tech pack usually shows up first as a launch date slipping, not as a quality problem.

How much is enough

A tech pack for a plain t-shirt is not the same document as one for an outerwear piece with fifteen components. Padding one out to look thorough helps nobody.

The test worth applying to each section is simple: if this were missing, would the factory have to guess? If yes, it belongs in. If the factory would do the same thing either way, leave it out.