Global Parameters are often overlooked in Revit but can be extremely useful. So what are Global Parameters?
Lets use an example. In the sample Revit project “RAC_basic_sample_project.rvt”, we have a number of windows on Level 1 which we are going to control the Sill heights at a project level.
Using a Global Parameter on the Manage tab we will create a new parameter.
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Clicking the New Global Parameter button I will use the following settings:
Name: Sill Height
Discipline: Common
Type of Parameter: Length
Group Parameter Under: Dimensions
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Clicking OK will create the new Global Parameter. Currently it has a value of 0.0 but I am going to change this to 100.
Selecting one of the windows on Level 1, I will click the Associate Global Parameter button next to Sill Height in the Properties window.
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From the list select Sill Height and click OK, the Sill Height property will now grey out as it is now controlled globally.
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You will also notice that the window has updated to have a Sill Height of 100 just as we set in the Global Parameter.
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I can apply this Global Parameter to all windows which need to match Sill Height.
Changing the Global Parameter again to 200 will now also update all the windows instantly to a Sill Height of 200.
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