> For the complete documentation index, see [llms.txt](https://docs.dietrichs.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.dietrichs.com/tutorials/tutorials-en/learning-the-basics/exploration-journey/dietrichs-item-number-catalog-rules-and-reference-sheet.md).

# Dietrich's Item Number Catalog — Rules & Reference Sheet

### What the list is

The catalog is Dietrich's standardized numeric classification for every structural component (known internally as *Stab-Nummern* / *Bauteil-Nummern* — beam type numbers). Each component created in the software carries a specific item number that identifies its functional role in the structure. As stated in the ABC Guide §26, "Each part is created with a specific Item number and carries its information further on into lists, plans and machine files."

> **Source:** *Dietrichs\_ABC\_EN\_03\_2021\_RZ §26 — HRB Wall Guideline Editor and Construction*

***

### Rule 1 — The number itself is hierarchical and meaningful

The numbering follows a **hundreds / tens / ones** pattern:

* **Hundreds digit = Functional zone** (100 Rafter, 200 Hip/Valley, 300 Plate, 400 Tie, 500 Floor Joist, 600 Wall Member, 700 Truss, 800 Batten/Sheathing, 900 General)
* **Tens digit = Subfamily within the zone** (e.g. within 600: 610 Verticals, 620 Horizontals, 630 Struts, 640 Beams/Lintels/Sills, 650 Log-home, 660 Blocking, 670 Stiffeners)
* **Ones digit = Specific component role** (e.g. within 610: 611 Post, 612 Stud, 613 Corner Post, 614 Door Post, 616 Window Post)

The group number (e.g. 610) functions as a *filter target*; the leaf number (e.g. 612) is what an individual part receives.

> **Usage in filters:** Postprocessor group specifications accept lists or ranges of these numbers — e.g. `3/4/6/-2/-3` for individual groups, or `-2..3` for a range. **Source:** *Postprozessor Guide §1.5.8 — Group dependent functions*

***

### Rule 2 — Assignment is automatic, driven by construction context

Users rarely type item numbers directly. They are assigned by the module that creates the part, based on *where* and *how* the part is placed:

* **D-CAD manual entry** — the beam function you pick carries the item number into the part
* **Automatic construction** (HRB Wall Guidelines, Roof, Floor Deck automatisms) — the guideline/ruleset assigns the number based on the component's role in the generated assembly
* **Profiles** — profiles instantiate components with item numbers defined in the profile template
* **Logic Blocks & SmartTags** — read existing item numbers and apply operations conditionally

The HRB Wall Guideline Editor is the primary rule source for wall components: it defines the components and their properties in a construction guideline, and assigns the appropriate item numbers when walls are generated.

> **Source:** *Dietrichs\_ABC\_EN\_03\_2021\_RZ §30 — HRB Wall Guideline Editor*

***

### Rule 3 — The same piece gets a different number depending on role

Item number reflects **structural role, not geometry or material**. Identical lumber receives different numbers based on context:

| Physical piece                      | Role in structure           | Item number                            |
| ----------------------------------- | --------------------------- | -------------------------------------- |
| Horizontal member at bottom of wall | Permanent bottom plate      | **621** Bottom Plate (*Schwelle*)      |
| Same piece                          | Temporary construction sill | **623** Sole Plate (*Montageschwelle*) |
| Rafter geometry                     | Normal roof rafter          | **111** Common Rafter                  |
| Same geometry, flying past wall     | Structural overhang         | **112** Overhang Rafter                |
| Same geometry, decorative only      | Non-structural              | **113** Blind Rafter                   |
| Beam between posts                  | Mid-wall horizontal         | **641** Wall Beam                      |
| Same beam, above opening            | Structural lintel           | **642** Lintel                         |
| Same beam, below opening            | Sill under window           | **643** Sill                           |

***

### Rule 4 — Chamfered / tilted variants get their own numbers

Where cut geometry changes significantly, Dietrich's assigns a distinct number so downstream CNC and list logic can branch:

* **131 / 132 / 133** — Tilted Slanting Rafters, distinguished by chamfering
* **315 / 316 / 318** — Chamfered plate variants (*abgegratete Pfetten*)
* **331 / 332 / 333** — Rising Purlins, split by chamfering treatment

This matters for BTLx/BVX export and postprocessor branching.

***

### Rule 5 — Item numbers are the primary filter key across the whole system

Virtually every Dietrich's subsystem uses item numbers as its hook:

**Postprocessor rules** — Material-dependent and group-dependent functions target item numbers or ranges to control nailing rows, restricted areas, and drilling behavior. The `Beam without nailing` function, for example, completely excludes a beam with a specified item number from nailing.

> **Source:** *Postprozessor Guide §1.5.8 — Group dependent functions*

**Sorting — beam-type-dependent sorting numbers (V19.01+)** — Reserve sequence-number ranges per item number group. Purlins can be forced to sort within 100–140 while rafters, hips, valleys, and ties start at 141 or higher. Syntax: `from/to` entries such as `320-323` (all canted non-rising purlins) or `331-331` (rising purlins only).

> **Source:** *V19.01 Update §3.7.2 — Bar type dependent running numbers*

**SmartTags** — Conditional operations applied based on item number and other component properties.

> **Source:** *Dietrichs\_ABC\_EN\_03\_2021\_RZ §65 — SmartTags*

**Sorting Number function** — The general Sort function; depending on beam type, sequence number ranges and specific fixed numbers can be assigned.

> **Source:** *Dietrichs\_ABC\_EN\_03\_2021\_RZ §67 — Sorting Number*

**D-Load (Load Planning)** — "Component types from 'Individual components' group" filter uses item numbers to control which parts load as individual components vs. as part of elements.

> **Source:** *Loading Planning Guide §5.6 — Individual parts*

**Wall Guidelines variables (V22.01+)** — Wall-layer item numbers are exposed as variables `LInp0`, `LInm1`, …(partner walls: `A_LInp0`, `A_LInm1`, …) for use in conditions like *"If slice item number contains OSB, then…"* — letting sheathing behavior be controlled directly via item number.

> **Source:** *V22.01 Update §3.13 — Wall guidelines*

**Connection-type filters** — Connection types in the wall guideline editor filter single objects by item type, beam type, designation, and groups.

> **Source:** *V22.01 Update §3.13 — Wall guidelines (connection types)*

***

### Rule 6 — Replacement Item Numbers are a *separate mechanism*

Do not confuse the structural item numbers in your catalog with **Replacement Item Numbers** introduced in V19.01. Replacement item numbers let a material-level item number (e.g. `OSB`) be automatically refined at sort time to a dimensioned variant (`OSB/3 22mm`) based on the component's actual thickness.

* The original item number is preserved in square brackets in object info: `"OSB/3 22mm [OSB]"`
* Replacement happens during sorting, not at creation
* Filters in intersection sets, Type4 edits, and SmartTags still reference the **original** item numbers, not the replacement

> **Source:** *V19.01 Update §3.7.4 — Sorting: Replacement ID numbers*

***

### Rule 7 — The 900-series is the escape hatch

The 900-range exists for parts that don't fit any functional schema:

* **900** General Beams (non-specific)
* **950 / 960 / 970** Vertical / Horizontal / Diagonal general members
* **951 / 961 / 971** Generic Post / Beam / Brace

These carry no semantic information and will be invisible to most rule-based automation. Use sparingly — they bypass guideline rules, postprocessor group filters, and D-Load grouping.

***

### Rule 8 — Module-specific number reservations

| Number range   | Module / Context                                                                                                |
| -------------- | --------------------------------------------------------------------------------------------------------------- |
| **180–182**    | Support Truss Timbers (*Widerlagerhölzer*)                                                                      |
| **650–652**    | Log Home Construction — only generated by Log Building functions                                                |
| **800-series** | Battens, Sheathing, Panels — driven by roof covering and wall layer definitions                                 |
| **830–843**    | Sheathing and Thermal Insulation subfamilies                                                                    |
| **850–862**    | Sheet materials (incl. CLT 853, Plaster Base 854, Function Panels 860–862)                                      |
| **920–922**    | Function Objects — logical placeholders (Load Room 921, Substitute Representation 922), **not** real components |
| **990–991**    | Armature / Tension Ties — hardware, assigned by the hardware library                                            |

> **Source:** *Dietrichs\_ABC\_EN\_03\_2021\_RZ §26 — Floor Decks, §30 — HRB*; *Loading Planning Guide §6.3.1 — Representation of loading components*

***

### Reference documents (project knowledge)

| Citation used above                   | Full filename                                             |
| ------------------------------------- | --------------------------------------------------------- |
| ABC Guide §§26, 30, 65, 67            | `Dietrichs_ABC_EN_03_2021_RZ_ind_-_Wil_Dancey.epub`       |
| V19.01 §§3.7.1, 3.7.2, 3.7.4          | `Microsoft_Word_-_V_19_Update_de_-_Wil_Dancey.epub`       |
| V22.01 §§3.13, connection types       | `V22_01_Update_description_-_Lindner_Johann_Baptist.epub` |
| Postprozessor §§1.5.8, 1.5.9          | `Microsoft_Word_-_Postprozessor_-_Wil_Dancey.epub`        |
| Load Planning §§5.6, 6.3.1            | `Loading__Planning_1_20_FSt_SAp5.pdf`                     |
| General Help 2025 (general reference) | `General_Help_2025_.docx`                                 |

***