Revit 2023 Demolition Problem

[moodyj2000]

So the new version has added the ability of demolished MEP elements to maintain their categories in response to multiple request on the ideas forum.  Works great except for one major issue.  To keep the system type the developers also physically are keeping the demolished element connected even when not visible.

The example I ran into was a project where I need to demolish all ductwork downstream of an existing terminal unit to allow for new ductwork to be installed in a new phase.  Downstream ductwork was set to be demoshed in the new construction phase and that worked well.  The problem is that when I went to connect the new ductwork to the terminal unit you cannot connect it as the demolished ductwork is still connected in the Revit DB.  This is a major issue as we do work on existing facilities all the time and up until now this was not an issue.  

[RobDraw]

Obviously, you need top disconnect the demolished duct in order to connect new duct to the existing to remain. The demolished duct doesn't need to be connected. The old demolish behavior disconnected everything. It's the lesser of two evils. If you don't like it, you could chalk it up to "be careful what you wish for..."

[moodyj2000]

I think I would rather push to get Autodesk to get the functionality correct versus accepting another 10 years of work arounds.  This issue will present far more challenges than what was happening before.  I rarely had to back up and un-demolish a system to a point where having it still connected would be a benefit.  I routinely break into existing piping and ductwork systems to connect new sections or equipment.  

Yes, not actually connecting the to be demolished ductwork is a solution but it is a bad one and continues the past habits of just working around things than actually trying to make them work.  

[RobDraw]

IMVHO, the previous functionality worked and made sense but opinions don't get heard here.  Go to Product Feedback or the IDEAS forum and remember that your opinion on what is right can be quite different from others.

[iainsavage]

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@moodyj2000 wrote:

This issue will present far more challenges than what was happening before.  I rarely had to back up and un-demolish a system to a point where having it still connected would be a benefit. 

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Totally agree. I would have left it the way that it used to work.

Most of my projects involve some element of refurb and we are routinely connecting new parts to existing systems.

So do we now have to manually disconnect demolished items in order to connect new to old?

[moodyj2000]

That is what I am seeing. I have played with it all morning and cannot find a way around it except to do exactly what you said. Even when demolished they are still physically connected and you cannot connect anything.

[Max_Space]

How I can connect to the coupler connector to which the pipe was connected before, but it has been demolished. Is it possible in version 2023, there was no problem with it before. As I read what you write, I recognize that now I have to disconnect every branch that is demolished, this is ridiculous.

[moodyj2000]

That is what I used to do as well. Worked great. I just finished up a piping and ductwork project and had to turn off auto-connect (it tries to connect it somewhere but gives an error because nothing is available), draw the new ductwork right up to the existing coupler, and live with the sad looking graphics when two things touch but are not connected. Definitely frustrating.

[RSomppi]

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@moodyj2000 wrote:
draw the new ductwork right up to the existing coupler, and live with the sad looking graphics when two things touch but are not connected. Definitely frustrating.

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This sounds like the way it used to work with everything getting disconnected. What were you doing before?

[iainsavage]

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@moodyj2000 wrote:
draw the new ductwork right up to the existing coupler, and live with the sad looking graphics when two things touch but are not connected. Definitely frustrating.

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The problem with that is that there is no system connectivity, its only a graphical solution.

With the old method undemolished parts of existing systems could be reconnected to new systems and the whole system would function correctly.

They’ve changed the method because people wanted demolished parts (scrap metal) to retain system data and now it seems that you can no longer connect retained existing parts back into new systems (which happens on about 75% of my projects) so I’m going to have to play about with this and figure out some sort of workaround.

[moodyj2000]

That is the frustrating part. Personally, I try to use everything with systems as correctly as possible. Revit is not perfect but it has come a long way. This eliminates any possibility of actually using the capabilities of Revit for calculations, sizing, etc..

[RSomppi]

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@moodyj2000 wrote:
This eliminates any possibility of actually using the capabilities of Revit for calculations, sizing, etc..

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Eliminates? Are you sure it's not just a matter of finding a different workflow?

[moodyj2000]

Eliminates is the correct term. No different workflow is going to correct the fact that two ducts cannot be physically connected to each other. Same for pipe. If they are not connected system level calculations will not work. They cannot be connected because the change in how the developers chose to handle demolished components does not allow for future connections. Don't see how you can work around that. You are either cheating the demolition or cheating the installation and for what my partners and myself pay for our firm to use Revit this should not be the case. I understand the intent of the direction they went but it comes at too high of a cost in other capabilities.

[RSomppi]

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@moodyj2000 wrote:
They cannot be connected because the change in how the developers chose to handle demolished components does not allow for future connections. 

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Then why demolish it in the first place?

[moodyj2000]

I am not asking this to be a jerk in any manner. Do you actually do mechanical design? Our firm does about 100 to 200 mechanical projects a year ranging from $10,000 to $400M in budget. Of those about 40% involve some type of demolition where you have to remove a section of duct or piping to allow for the installation of a new section of duct or piping. We have to produce demolition drawings to show contractors what has to be removed and then produce new work drawings to show them what to go back with. This is industry standard practice and the reason why the ability to accurately show demolition is key.

[RSomppi]

I'm not getting into a pissing match with you. If you are doubting my experience, then this conversation is over.

[RobDraw]

Why are you demolishing ductwork that you plan on reusing?

[moodyj2000]

It's not what is being demolished. The problem is with what remains. Here is a simple example. You are doing a renovation in an existing locker room. The architect wants to re-partition the space. You have an existing roof mounted exhaust fan and ductwork running through the space. They mark all walls for demolition. You mark all the ductwork back to a point as being demolished. On the new work plan you want to connect new ductwork to the existing ductwork that is remaining. Revit 2022 and prior you can do this. Revit 2023 you cannot. Revit still thinks all the ductwork selected for demolition is connected and will not give you the option to connect anything to it.

Another example. Existing office space with existing variable air volume terminal units. The architect is demolishing the existing walls and re-working the floorplan. The project requires you to demolish all low pressure ductwork downstream of the terminal units. New work plans requires you to route new ductwork from the existing terminal unit to new grilles. Once again, because 2023 thinks the demolished ductwork is still connected you cannot actual connect new ductwork to the existing terminal units.

We run similar scenarios to both of these examples every week in our office. So not trying to use the ductwork we demolished. Trying to connect to what remains is the problem.

[RobDraw]

That's a pretty long winded way of saying what's already been said. The problem with your previous comments was too many words that made it sound like you wanted to reuse the demo duct. Yes, the new functionality of the demolition tool does require you to disconnect. The old way disconnected everything and removed system information. I didn't use the old demolition tool and opted for making a demolition phase which required disconnecting from the existing to remain.

So, it seems Autodesk has determined that this is what the users want which is sometimes a problem with satisfying the complainers that can't see the bigger picture. The silent majority loses.

As to your comment about losing the ability to use calculations, you couldn't be more wrong. The functionality is still there if you use a proper workflow. Just because disconnecting is beneath you, doesn't mean the functionality has been eliminated. 

[iainsavage]

@RobDraw could you describe the workflow for the benefit of others? To disconnect do you have to grab the ends of the ducts, pull them apart and then use the Divide System tool? Or do you use the Split tool then delete the union and then divide system? What’s the best way to do it?

I’m genuinely interested in a constructive answer to this problem and hoping that this thread doesn’t end up like some of the previous ones on the topic of demolition.