Mark – Instance Numbering

The terminology in Revit for Number is Mark. Typically it is the instance parameter used for numbering items like doors and windows. The mark parameter is a system instance parameter and acts a little bit different to other instance parameters.

1^st This value must be unique for each element in a project. Revit Architecture warns you if the number is already used but allows you to continue using it. You can see the warning using the Review Warnings command.

2^nd When a element is grouped, the mark parameter (along with phasing) is one of parameters that can be changed. This means if you come up with a user made instance parameter for example; door number, it won’t work if the door is grouped.

3^rd Some category elements will automatically number the elements as you put them in the model. So as you insert them it will number them sequentially. The Architectural categories that give an actual number to the element include:

Doors

Electrical Equipment

Electrical Fixtures

Lighting Fixtures

Mechanical Equipment

Plumbing Fixtures

Windows

It should be noted thought; even though Revit does not actually put a number on the other categories, it still knows the draw/insert order. If you create a schedule and sort it by Mark, despite the cells being blank the sorting order will be correct. So it’s just a mater of putting the numbers in manually.