Fire alarm addressing in Revit: detector groups and loops without the handwork

Fire alarm addressing in Revit: build detector groups, fill loops, produce the cable list — room-aware instead of by hand.

DIN 14675VDE 0833-2

Where the design work stalls

The model is there, the detectors are placed, the ceilings are covered — and then comes the part nobody enjoys: addressing. Every detector needs its group, every group needs its loop, every device needs an address, and at the end a cable list has to come out that the installer can actually read. In a mid-sized building that is several hundred devices before you have finished counting.

The volume is not the real problem. The problem is that the assignment is not free. A stairwell runs through several storeys and still belongs together. A corridor is an escape route and is treated differently from an office. A shaft is its own area. Manual call points must not sit in the same group as automatic detectors. And when a group is full the next one starts — but preferably not in the middle of a room, and certainly not with a group torn across a loop boundary.

Do this by hand and you are keeping a list in your head while you click. That works for a while. It works right up until the architect moves a wall and one room becomes two.

How it is usually solved

The common route is a spreadsheet next to Revit. You export the detectors, sort them by storey and room, hand out group and loop numbers in Excel, and write the values back into the model through a schedule or by hand. It works, but it has two weaknesses.

First, after the first design stage the spreadsheet is no longer the model. Every change has to be maintained twice, and which of the two versions is right often only becomes clear at handover. Second, the expertise — stairwell gets its own group, call points kept separate, capacity per group — lives in the head of whoever keeps the spreadsheet. Give the next project to somebody else and the result looks different.

The third route you occasionally see is plain sequential numbering in selection order. It is fast and the result is unusable, because the groups it produces have nothing to do with the building.

What the module takes over

The command BMA adressieren works on the selection — normally one fire compartment. It recognises the rooms by itself, from the rooms or spaces in the model and from linked models as well. This is where room-aware addressing parts company with sequential numbering: the tool knows whether a detector hangs in a stairwell, a corridor, a shaft, a lift or an ordinary room.

The grouping follows from that. Every stairwell forms its own detector group, and it does so across storeys — a stairwell is one area, not a stack of storey sections. Every shaft and every lift likewise gets its own group, and so does every corridor. Ordinary rooms are pooled per storey. On top of that the tool separates by class: ceiling detectors, void detectors, manual call points and sounders never share a group, and automatic and non-automatic devices are never mixed.

The capacity limits per group and the loop maximum are configurable. What matters is how the tool handles them: the loop only changes at a group boundary. A detector group is therefore never torn across two loops — precisely the mistake that manual numbering produces most often and that surfaces latest.

The values are written to the parameters GTech_Loop, GTech_Gruppe, GTech_Adresse and GTech_Kabel, and on request the recognised room to GTech_Raum. That puts them in the model rather than in a file beside it. If you want group numbers to follow a storey scheme — a base number per storey with sub-bands for void detectors, call points and sounders — you switch that on in the options.

Two more commands belong to the set. BMA-Kabelliste builds the run list from the values written. GTech beschriften places the tags on the sheet without you positioning them one by one.

What has to be right in the model first

The tool reads rooms, so rooms have to exist. That sounds obvious, but in an electrical model it often is not: the rooms usually live in the architectural model and are only linked in. That is exactly what the recognition is built for — it takes rooms and spaces from your own model and from linked ones. What matters is that the link is loaded when the command runs.

The second point is naming. Whether a room is recognised as a stairwell, corridor, shaft or lift depends on how it is named in the model. If your stairwells are called “TR 01” and your corridors “circulation”, check after the first run what the tool made of it — it lists the areas it recognised. Cleaning up room naming once pays off across the whole project, and not only here: the same rooms are needed later by the reporting module and by the cable list.

The third point is the selection. The command works on what is selected, and the sensible unit is one fire compartment. Select a whole storey by accident and you get grouping across compartment boundaries — computed correctly, wrong professionally. That is the most common operating mistake, and you can see it immediately in the number of groups produced.

When the design changes

The real gain does not show on the first run but on the fourth. A wall moves, one room becomes two, a detector is added. By hand that means: work out which group is affected, check whether it still fits its capacity, split it if not, and shift every following number. You do it carefully the first time and faster the next.

With the tool you reselect the area and run the command again. The rules are the same, so the result is built to the same rules — regardless of who is at the keyboard and how late it is. Then the cable list and the tags are regenerated.

For handover to the installer that is exactly what counts. The cable list is an evaluation of the model, not a second document somebody has to keep in step. What is on the sheet is in the list, because both come from the same parameters.

Standards

The module is aligned with DIN 14675 and DIN VDE 0833-2 — the two documents named for this tool in the shop. The grouping by stairwell, corridor, shaft and usage unit and the separation of automatic from non-automatic devices follow that system.

What the tool does not do: it replaces neither the fire safety concept nor the coordination with the fire alarm contractor and the fire service. It removes the mechanical work that sits between a finished concept and an addressed model. The limits per group and per loop are settings — they belong to the project and to the panel technology in use, not inside the tool.

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