The technical section of a tech pack communicates how the garment is constructed. It will always include a tech sketch which is the flat sketch from the cover page with seam, stitch, and detail callouts. Some details will have expanded close-up sketches or alternate views such as the sides or inside showing how those details should be constructed. The sketches will show how each edge is joined (what seam type) and with what technique (the stitch type). To further clarify the construction, I always use ASTM codes and diagrams within my tech callouts as most factories are familiar with these standards. The tech sketch page should also show or list the amount of seam allowance on each edge of the pattern.
Another page in the technical section will show what labels and hang tags are used for the garment. It will show the placement of the label on the garment as well as a mock-up of the labels showing their dimensions.
Packaging specifications are another page of this section. Once the garment is done, how do you want the factory to send it to you? Any poly bag, UPC labels, or boxing and shipping instructions will be included on this page.
The final page in the technical section is the sewing order. This section lists out each step of the sewing process to make the garment. The order of operations indicates how you want the garment finished. Some sewing orders are easier or cheaper, while others offer more stability or a higher end finish. It is best to have your patternmaker or samplemaker write the sewing order as they will be able to best determine what order is appropriate for your product and price point.
The technical sketch and construction section helps you the designer in several ways. Knowing what seam and stitch types are used in the style will help you when interviewing or deciding on a factory to make the style. Not every factory has every type of machine and by knowing what types of stitches and seams you need, you can ask upfront whether they have the necessary machinery.
Another benefit to you is that you are able to see what details and quality of finishes are in your product. Is it lined? Does it have double turn hems or single turn edge finishes? Are the sleeves set in or sewn on before the side seams are joined? Even if you don’t know how to sew, you can look at the tech sketch to confirm that all the design details and finishes you asked for are included in the final design.