Room stamp: the label the CAFM hooks into

What the stamp shows

The usual content per room is room number, room name and net floor area. Per storey, a stamp with the gross floor area is added. Which fields appear beyond that is set by the operator’s CAD guideline – some also require the type of use, the cost centre or the floor finish.

Why the room number is the most important part

The room number is the key. Through it, the CAFM system links the room polygon in the drawing with the data record in the room book. If it is assigned inconsistently or twice, the import fails – regardless of how well the drawing was made. That is why the numbering system is agreed before the survey and not afterwards.

In existing buildings with numbering that has grown over time, this is regularly the most time-consuming point of coordination in the entire project.

The room number is the key

Of all the details in the stamp, one carries the real load: the room number. It links the drawing with the room book, the room book with the CAFM data foundation, and that with every contract that refers to rooms.

This results in three requirements that sound trivial and are regularly violated in practice: the number must be unique within the building, it must not change, and it must be written identically in drawing and list. A room called “1.04” in the plan and “104” in the list is two rooms or none as far as the import is concerned.

Text or attribute

A stamp can sit in the drawing as labelled text or be attached to the room polygon as a property. Both look the same. Only the second can be evaluated.

If the information exists as free text, it has to be read back out of the drawing during import and assigned to the room – a step that is error-prone and recurs with every plan change. If it is attached to the polygon, it moves with it. That is why we deliver room polygons with attributes, not just text.

What the stamp should contain

• Room number, unique within the building
• Room name, i.e. the use in plain language
• Net floor area to DIN 277, with the edition stated
• Optional: floor finish and clear height, where they are needed in the plan

Little else belongs in it. Everything else is in the room book and is linked via the number – an overloaded stamp makes the drawing illegible without making the information any more accessible.

Where it goes wrong

The most common case is numbering that has grown over time: over decades, rooms have been split, merged and renamed, and several numbering schemes exist side by side – the caretaker’s, the one in the fire safety documents, the one in the leases. Which one applies is a decision for the client, not one we can make.

It is therefore made before the survey. If it is postponed, the result is a drawing set that meets three different inventory lists on import and matches none of them.