Export information to excel from specific families

Hello all,

I have been spinning my wheels for a while now and I need some help maybe getting pointed in the right direction. I am an MEP engineer and most of the how-to’s and tutorials are set up by and for architectural elements. Usually we can find a work around to get to the same results but this work flow has me stumped.

I have been asked to generate a dynamo script that takes all of the VAV terminal units in a project and exports there parameter values to excel, so that we might override the values and import the new values into the individual instances of the families. Unfortunately, the terminal unit family lives under the mechanical equipment element type and I am having trouble filtering the elements list down to just VAV units (getting rid of air handling units, plumbing equipment, exhaust fans, etc).

Can someone help me find a thread that already answers this type of dynamo script?

If this bridge has not been crossed yet, how might we filter a list of elements to a specific family?

Thank you in advance,


First question: do you have multiple VAV families within the project? (My recollection is that it’s usually one manufacturer family for a particular coil type [HW/Elec] up to a certain size where rectangular inlet connections are needed, then you pull in the ‘large’ family as well)

If it’s just one family, you can retrieve the family names of your mechanical equipment and filter by that name.

If it’s multiple families with a common naming system, you can attempt the same thing as the one family case but filter by the most common point of the name (hopefully it’s VAV or something intuitively unique to just your VAV families).

I would suggest try using add-ins like Kobi’s BIM Query tool for this option if your interchange between Revit and Excel is frequent. It’ll be worth your buck. If you’re struggling to understand the use of get and setparam, it’s quite dangerous for you to execute the full script. Not paid to recommend this. Just one of their users. :slight_smile: hope that helps.

Or Export-Import Excel from BIM One.


We have multiple “VAV families” but we are looking for one specifically. We have one family that is for single duct terminal units. The Parent family has multiple variations within the family based on neck size (4", 5", 6", 8", 10", 12", 14" and 16") and each neck size variation has three options (basic damper only, with reheat, and with reheat and a sound attenuator). We do not have multiple families for type of reheat, electric versus hot water, they live in the same family and we manipulate the final schedule to reflect reheat type.

At the end of the day all of these variations populate the same terminal unit schedule and we would like to manipulate all of the single duct airflows (cooling max, min, and heating max), and capacity via excel since we do all of our HVAC calculations in excel.

Thank you,

You can use Family.ByName to get the VAV family you’re looking for and then Family.Types and FamilyInstance.ByFamilyType to get all the instances in the project.

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