Flow rate from a pipe fitting (I really need a help)


Hi guys…

I have a question about pipe fittings…

If I have a domestic water system which is connected to some Sinks, Do you think is it possible to see the flow rate (or the Fixture Units) for the pipe fittings (Bends or Tees) with Dynamo?

I would like to use Dynamo to size pipes and pipe fittings with an equation Pipe size=f(Flow rate) or Pipe size=f(Fixture Units).

With the pipes should be an easy job but what about pipe fittings…?

Thanks for your help guys… indeed!!!



If you can get the values for the pipes, why not just then look at which pipes the fitting is connected to, then get the flow from those pipes and use it in the calculation for the fitting in combination with the .

You can either use Element.Geometry and DoesIntersect to find which elements are connected, or you can dive into the API and find what the Connector Set-Owner Element is (this will tell you the Element IDs of the pipes that are connected to that fitting).


Hi Ben,

Thank for your answer…
omg… it’s getting more complicate so I guess…

Unfortunately I’m really new with both Revit and Dynamo…
Can you help me a little bit more?

Let’s start with an example…

I have 2 WC. each Wc has 1 Fixture Unit. (see pic)

I want to supply them with cold water.

If I use Dynamo:

  1. How can I find pipes just for the cold domestic system (In Dynamo)?

  2. How can I see the fixture units that the pipe has (in Dynamo)?

  3. I can’t find “Element.Geometry” and “DoesIntersect” in the library (in Dynamo)… Do I have to download them? where?

Thanks Ben…



See image below for answers to your 3 questions:







Note that the element.Geometry only produces “medium” level geometry, so that procedure I suggested may not work out quite like you wanted. You may need to explore the API solution.

If you are really just new to Revit(< 6 months), I applaud your bravery in trying to learn Dynamo concurrently with Revit. That said, have you looked into the native “Duct/Pipe Sizing” tool in Revit? That might do what you are looking for ( I say “might” because I’ve heard (I’m a structural engineer, not MEP) that it might not calculate what hand calcs would come up with, and many engineers are hesitant to trust a tool that is not producing a similar result ).

Also - Any Dynamo Experts know why the toilets appear as “beehives”. This is the base plumbing template from the install library…


Hello Ben, could you please upload your screenshot in bigger size? Thank you in advance


The screenshot size is a consequence of the forum changes made about a year and a half ago. I’d suggest starting a new thread asking whatever question you have (I do not have the screenshot from 2 years ago still…)