The Single-Model Principle
In Tekla Structures, there is one model and all drawings come from it. A column size is a model attribute — it appears on the column drawing, in the BOM, in the bolt list, and on the erection drawing because they all read the same database entry. If the column is revised, all associated drawings update. This eliminates the most common 2D detailing error: manually updating a member size on one drawing sheet and forgetting to update it on three others.
Automated Dimension and Connection Extraction
Dimensions in 3D detailing are not typed — they are extracted from the model geometry. The distance between two hole groups is calculated from the model's geometry, not from a drafter's measurement. This means dimension errors can only be introduced at the model level (wrong geometry) — not at the drawing level (wrong number typed). If the model is right, the drawing is right. If the model is wrong, every drawing derived from it is consistently wrong — making errors easier to find and correct systematically.
Connection Geometry Validation
3D modeling allows connection geometry to be visualized from any angle before drawings are extracted. A connection that looks reasonable on a 2D plan view may have a bolt that is physically inaccessible from a 3D perspective — hidden behind a flange, inside an HSS, or blocked by a gusset plate. Tekla's connection components validate bolt access clearances and flag minimum edge distance violations — checks that are impossible in 2D drafting and require experience to catch by visual drawing review.