Revit has a built in function that can let you know in which space an air terminal is located. Rhythm has a great node: ‘Element.Space’ for this. Unfortunately most other elements that you’d like associated with a space don’t have access to this space information. The node ‘Space number to network concatenate’ can assign the air terminal’s space number to every upstream element in the connected duct network. While traversing it will concatenate every space number into the parameter with a comma.

The node will stop traversing once it can no longer find an opposing flow direction, encounters a different system classification, encounters an element it has already encountered (and thus has entered some kind of loop) or there is nothing connected to the current element.

Inputs:

• Air terminal: the starting air terminals from where the traversal into the duct network will start.
• ParameterName: the parameter of the elements in the duct network to which the space numbers will be written to.
• Category: only elements of these categories will have their parameter written to. Supports multiple categories.
• SizeLimitFactor: an optional input that controls how far into the network the parameters will be written. The node will stop when the element’s size in the network is ‘factor’ times as big as the starting size. The default is set to 20.

Output:

• The input elements are returned unless the air terminal is not located in a space, in which case a string indicating no space is found is returned.

The node can be found in the MEPover package version 2017.2.13 and up.