Rule Value Definition

The Value Definition part of the Edit Rules dialog is where the new value for the Target Parameter is defined. Use the “Add a Part” section to mix and match any or all of these parts to make your own custom Rule:


The Constant is a Rule part that provides a way to add text or number values that are intended to be the same for all selected elements. A common example of a Constant is to use “L1”, “1”, “1-”, or “1.” to prefix the value for elements that are on the first floor level. In the Parking Rule, the Level is a Constant. Double-clicking on the Level will open the Set Constant Value, as shown, and let you adjust the settings. Related settings: Prompt for value and Name.


The Value field is the default value that will display in the main dialog box when this Rule is used. In the Parking example, shown above, the value is “P1-”, meaning that all selected Parking elements will be numbered using first the “P1-” text.  

Prompt for value

The value of the Constant can be altered within the main dialog if the “Prompt for value” checkbox is selected. For example, if “P1-” is specified in the Rule, and the “Prompt for value” checkbox is not selected, this text will always be used. If the checkbox is checked then the person numbering the Parking elements will be able to change the text from “P1-” to “P2-” or “P1.”, etc.

TIP: The value can also be deleted, making the Constant optional to the end user.

Constant Name

The Name of the Constant only applies if the “Prompt for value” checkbox is selected. The value of the Name field is displayed as the label on the main dialog.



The Increment is a Rule part that is used to increase a number or letter value with each subsequent element. Increment numbering is the Revit method for numbering all Mark values: if the first Door is 112, then the next will be 113. Use the Increment button under “Add a Part” to add an Increment to a new Rule. Each Rule is allowed only one Increment part.  

The settings for Increment parts, as shown in the dialog below are: Name, Starting Value, Increment Per, and Leave Singles Blank.


  1. Use an Increment part along with a Room- or Space-based Field part to enable the Auto-Update numbering method.
  2. Rules without an Increment, such as the one noted below under the Field topic, are also supported by Auto-update numbering.

Increment Name

In the example shown below, which comes from the Doors Rule, the Increment is Named “A”. The Name is used internally within this dialog only for identification purposes.

Starting Value

The “Starting Value” is the default text value (for the Increment portion of the Rule) that will appear in the main dialog when the Rule is used.

Increment Per

The “Increment Per” option is available as a way to force a re-set of the Increment value based on the Room, Space, Level, Family, or Type property. In the example shown above, the value of the Doors Mark will reset to -A whenever the Room changes.

Leave Singles Blank

 This option only applies when the “Increment Per” choice is set to something other than “None”. When checked, this option allows elements that only have one instance per the “Increment Per” setting, to ignore the Increment. If you are numbering Air Terminals per Space and the first space has only one Air Terminal it will be numbered without the increment (e.g. 101). If the next Space has three Air Terminals they will be numbered with the increment (e.g. 102-A, 102-B, 102-C). 


The Field is a Rule part that is used to reference a property of the element. For example, the Bonus Rule called “Viewports — Update View Name”, shown in the image below, uses (3) different Fields to create a new value for the View Name parameter: Sheet: Number, Detail Number, and the View Name (itself). 

Submit feature or issue request for Ideate Software

Thank you for taking time to inform us about a bug or feature request.

If you'd like to upload a file to help explain the issue, you can upload a file to Hightail.