Get Parameter By Name

A very commonly used node to read element parameter values in Revit is the Get Parameter Value by Name node. Search for "getparameter by name" to find the node. Notice how the words "get" and "parameter" do not have a space in between them to retrieve the correct node every time.

This node has two inputs, "element" and "parameterName". The first input is an element or list of elements which you would like retrieve parameter values from, and the parameter name is the name of a parameter associated with the element. Note that the parameter name is case sensitive.

One of the ways to get started is to use the Categories node and All Elements of Category node. These nodes is typically used to retrieve elements in the model.

For example, let's find the family and type names of all the walls in the project. Choose "Walls" in the Categories node, and type in "Family and Type" in a string node. Add a watch node at the output to view the results on screen or simply drop down the results when the process is done. Connect the nodes as in the snapshot below and run the graph. You will have quickly retrieved all the family names and family type names of all the walls in your Revit model.

You can find other useful information of by changing the name of the parameter, such as "Base Constraint", "Unconnected Height", & "Area" which are some out-of-the-box parameters in Revit. Other project parameters added to the model can also be retrieved, such as "Fire Rating" or "Finish Type" which are typical parameters added to walls. Make sure to use the exact name of the parameter associated with the element by checking the Properties window.

Notice how some parameters don't return useable information such as "Phase Created" and "Phase Demolished". The results are actually the element IDs of the phases. In order to read the names of the phases, other nodes are required. ElevateBIM recommends using the node Name+ in the Clockwork package. Make sure you have the latest version of the Clockwork package installed, and search for "Name+".

One very helpful node to help you understand what parameters are available in the elements is the Parameters node. Search for "element.parameters".

Connect your elements list to the input node and run the graph again.

Once you are more familiar with Dynamo, you can use other nodes to filter down the specific elements you wish to read element parameter values, the specific names of the parameters you wish to read, and also specific ways on how to read those parameters correctly.

Download the Dynamo graph at the links below for your own use. You may also visit Autodesk's sample project page to download sample Revit models for your own practice. In this post, the file "rac_advanced_sample_project.rvt" was used. As a disclaimer, ElevateBIM has no affiliation with Autodesk. These links are purely for your own convenience.