Automatic dimensioning of families

I would like to make a script to automatically dimension families between each other and connecting to grid lines. However, every post that I read on this site seems to involve pulling in model lines from family and then dimensioning those model lines. However this concerns me because wont this break the connectivity to the actual revit family and the dimension? Meaning that if the family is moved, then the dimension will not? Or am I missing something. Id like to know if dimensioning bi-bidirectionally parametric dimensions are even feasible before I start writhing this script so that I dont get caught in a dead end. If it is possible, can you please give me a hint as to how? Like use reference planes or something. I should be able to take it from there. Thanks!

I can confirm it is doable. :slight_smile:

You’ll have to build it though. Dimensioning is not for the faint of heart.

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BIM manager of our team was wonder-stricken at BIM expo in Munich. He said that he saw nobody presenting an addon for annotating projects. Annotations are placed by hand, because you never know what it is exactly that you would wanna annotate. Imagine a machine which can read your thoughts. That would be an addon for annotation.

Such add-ins exist though, and are quite successful.

Some examples are below. The key to each of these is that they are a specialty for a single task not a generalized tool, they are typically heard at the ‘primary information on the page’ not all the information which we wish to convey for the project, and the code to automate such usually is developed for them and to their standards as there isn’t such a thing as a consistent global industry standard for most of them.

  • Manufacturer of building systems like can automate the dimensions for each piece in an equipment run.

  • MEP fabricator can automate the plan layout of each sprinkler head relative to the room it is in.

  • Landscape designer can automate tagging all plantings by species and area

  • Structural engineer can tag and dimension the columns to each grid line.

  • Architect can dimension the stair section with the standard annotations for tread, riser, guardrail height, handrail height, baluster spacing, baluster start point, etc.

  • And of course there are the existing bulk tools already built in Revit (tag all, tag on placement).


Well ok, but each example you gave is a very specific object of annotation. My boss wanted an AI that would learn from us and do everything for us :rofl:

Yes different scopes for sure. That said I have seen some very impressive ‘annotate this view’ tools which are AI driven, but they still miss as much as they get.

The reason for the misses isn’t because of the inability for the AI to to the task, but because the underlaying data is too inconsistent to work. AI doesn’t scale in a working environment until you have more than 1,000 full sets of a single typology where there is not a single instance of a user:

  • leverages text instead of a tag
  • uses lines instead of
  • uses a different parameter than the office standard
  • loads in a different family so it looks better

Until then it might not annotate your walls fire rating, or might pull it from the sound rating instead.

In general the generalists of AEC have failed to capture their decision logic or deliver to a consistent standard. Until one of those two things changes your boss will continue to have to pay you and your colleagues to do some decision making.

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Its not just about paying people to make decisions, its about making best decisions. One of my college’s is an elder architect. He took advice from an AI. It was something about the building facade. I synced and saw it. So, I came into his office (not knowing what he actually did), and started criticizing “his work”. We opened the subject, and looked for alternatives. Finally, he was the one who suggested the solution that we both like. He explained the AI story and admitted that his alternative was better.

AI will never do what we actually need, because it is impossible, and unnecessary.

If your coworker asked an AI today it is likely that he was utilizing a GPT system, which will not work for what he was after (or for design in general). Some for of AI will be introduced to do what you were after during our lifetime. The current tools are just light years away from what they will become (and likely will utilize methods besides the general pretrained transformers of today).

I am doing scripting in dynamo for annotations and tags in fabrication drawings. It works but need to follow a strategy and many test trials until finding right positions not clashing between anything and readable in paper, very complicated :thinking: :confused:

Once that machine exists your boss might not need you, or anyone else for that matter… heck eventually the clients might not even need us unless we transform our services. Imagine a future where AI generates a majority of a construction doc set and clients just pay for an architects stamp - it’s a grim future for firms charging per hour/drawing in fee calcs (most of them). It might seem far fetched but it basically happened to building cert once searchable standards hit the game.

I’d suggest checking out Glyph which is decent at annotating and dimensioning. It wont learn from you though, if your boss is serious about a business specific solution they should begin inhouse RnD and hire some computer scientist types.


Continuing the fantasy:

AI is not specific to the construction industry anymore. It learns about everything. It generates new boolean type of data, and names it: Truth.

Like True/False, Truth has one of only two available values: Good, or Evil.

AI starts to assign Truth as an attribute to everything. People who doubt their own will are looking for answers from the ultimate Truth generator, and the words of an AI start to spread among people like a virus.

Other people feel their free will is being judged, and threatened, or feel sad for the indoctrinated. They name the AI: Snake. Snake sees no color. It sees black, and white. It has no character compared to the other snake of its species. It is programmed by what is good, and bad for it. It has a poison of destruction, that can deliver by bite.

A war starts.

“Don’t eat from the tree of Knowledge of Good, and Evil, because on the day you taste it, you will die.”

a Key for encrypted war letter.

“Feel the AGI with in you” everything you say here is being absorbed and added to the AGI, thread lightly.