I’m having an issue where the interior walls in my model are getting treated as exterior walls when I set the boundary location at wall finish in my export settings because of the gap between the rooms. I’ve seen suggestions to set the boundary location at wall center to close the gap and resolve the issue, but I would like to keep the boundary location at the wall finish. Is there a workaround to keep the boundary location at wall finish and also keep the interior walls as interior walls? Thank you!
Can you help me better understand your use case here? There are more forgiving ways to model the walls as exterior in certain software. Which software are you trying to export your model to? e.g. is it EnergyPlus, IDA ICE, or IESVE?
Thanks! From what I could find online you only need the area when you create your model in CHVAC and you don’t need the adjacent wall and you only need the length of the rooms. If that is true I can think of a workaround that gets you there but I will wait for you to confirm this before I record the video.
What I’m thinking to do is to create a a temporary room where the wall thickness will be and then delete the room after importing the gbXML.
The other possible solution is to introduce a gap distance/tolerance to solve adjacency command for cases like this one. What do you think about this, @chriswmackey?
Thank you for the reply. CHVAC also takes any exterior walls of the rooms when doing the load calculation.
I also considered creating temporary rooms/spaces in the model where the wall thickness will be and deleting these rooms/spaces later, but I was hoping for something that could automate this process due to the scale of the model.
See this. It is not fully automated but it will be faster than drawing a room using the walls.
We can also probably put a script together to do the same. @chriswmackey is the better person to do that. How large is your project? Can you share the PoMF with us? That way I can test the script with your project. This is the second time that this request has come up.
Hi mostapha, thank you for putting the video together. This is very helpful. Unfortunately, I’m unable to share the PoMF due to the confidentiality of the project.
Sorry for being late to respond here and I am glad that you were able to come up with a workaround.
Because the “Solve Adjacency” command is intended for the case that you want split walls with one another so that there are equal wall areas between adjacent rooms where correct heat flow can happen across them, a gap distance doesn’t’ really fit with this operation. Really, what you would be doing is changing the model tolerance, which you can already do right now in the model editor. But, as your intuition would probably tell you, making your model tolerance this coarse can make a mess of your geometry and so I would not recommend it.
If it would help, I could add a separate command that performs no splitting of any geometry but just senses if a given wall is within the gap distance of another room. If so, the boundary condition of the wall gets set to adiabatic. This would require you to do some manual insertion of vertices in some cases but it should basically achieve the desired set of outdoor boundary conditions that cHVAC likely wants.
The other approach if the current workaround is tedious, is that I can add a new command that does the whole process of creating the interstitial room with one command. Basically, it runs “Create Boundary”, then “Create Room” and then does the boolean subtraction with the room selection.
Just let me know either of the above would be helpful and I can add it to my agenda.
Hi Chris, I’m not quite understanding why vertices would need to be inserted and which cases would require this with the first command, but the command to create the interstitial room would be helpful.