Room boundary bypassing column in wall

[Taase]

I really hope some can help me with this issue.

I’m working on a very large project (260.000 m²) in the early stages. Our walls and columns is just generic material at this point.

As you can see on the screenshot, we have a problem each time our wall meets a column. The column is build 45 mm into the wall. Every time we have a detail like this, the room bypasses the column and leaks into the next room. We have tried everything, from different materials, joining, and room boundaries and so on. The only thing the can prevent this from happening, is to draw a room separation line on both sides of the column, so the room separation line connect the wall and the face of the column.

Here’s the question:
Why does the bypass not occur then we move the column 5 mm more into the wall?

In this case, the wall is 400mm, but if we change in to 300 mm, and still have to column 45mm build in, the problem stops.

it seems like the smaller the wall thickness, the less the column have to move into the wall to stop the problem.

Does anyone have a solution for this?

[enslinj]

Hi there,

Could you please post that example file. (purge project to make it smaller)

I would need to look at the column family & the wall structure to assess how to solve problem.

Thx

Enslin

[Taase]

Here is a sample. i have made no changes to the column, it is just the standard. It is Revit 2014.

[enslin]

Wow!! 

That is very interesting indeed.

Did some tests & there is no difference between using an architectural or structural column.

Also, changing the wall structure & function does nothing either.

The only good news I can try offer you is a better way of creating the room seperation lines.

The room overflow happens at the edge where the column is inset by 45mm.

My advice, create one room seperation line on that in internal wall edge. (click pick lines) See image

It will solve your problem and since it automatically constrains to the wall it will move when the wall moves.

Not the ideal solution, but it will stop you from having to update room seperation lines everytime your model changes.

Interested to hear the solution on this one.

[enslinj]

Test Post. Strange, but reply above shows new memeber? Weird a
Anyway hope it helps

[Taase]

Yes it makes no sens to me at all, why this happens. Would be nice to have reply from autodesk, if this is a bug.

Yes, the room speration line along the wall i proberly the fastest solution at this point, even though i will trigger a Warning.

Thanks for testing 🙂

[Taase]

Does anyone know how to get a reply from autodesk? I feel like wasting my time is this is a bug that can be fixed.

[Taase]

This is still a problem. We are now on UR8, and the problem still exist.

[Keith_Wilkinson]

I would take from that that this maybe isn't an easy fix.  We've had the same issue on a number of projects and in varying conditions but all resulting in the same error and all related.  A room separation line sorts it but as was stated before this isn't ideal.

K.

[cbcarch]

Is the column set to be Room Bounding? Is the column Architectural or Structural?

[tamas_badics · Accepted solution]

Taase,

This is a known issue and is NOT caused by a bug. When last time we implemented major improvements to room calculations, we decided to use a somewhat simplistic but very robust approach of treating all walls as 1 foot wide. This can result in artifacts that you see here. The vast majority of models do not exhibit such problems.

We are aware of the issue and fully know what causes it. However the fix is not simple because it involves rewiring a fundamental calculation that supports rooms that are widely used. For now the best you as a user can do to work around them is to add a few extra room separation lines.

Hope this answered your question.

 Tamas Badics

Autodesk - Revit Development

[Keith_Wilkinson]

Thanks Tamas,

Can you explain a bit further?  What exactly do you mean that all walls are treated as being 1' wide and how does that result in what we are seeing here?

It would be good to understand fully what is going on so that we will have a better idea when this type of behaviour might be exhibited.

cheers

K.

[Taase]

Thank you Tamas

I fully understand that this is not an issue you can solve easily. Do you know if there are any other workarounds that adding room separation lines?

I am asking you this for this reason: That it will not be a few extra separation lines. Our building has 10470 rooms, and the column issue is present in a lot of them, resulting in inaccurate room calculations, or data that cannot be trusted.

[ToanDN]

What I read is when a column is outside of the 6" distance from the centerline of the wall, the program does not recognize that they are touching, and that causes the room bleeding issue. That is why 300mm wall worked, but 400mm did not.

[tamas_badics]

You are correct ToanDN. (Sorry for not responding sooner. I did not get notification on the other comments) Tamas

[tamas_badics]

Well, there is not a whole lot you can do. You could make your columns not room bounding but I suppose that is not really desirable as the reported areas will be incorrect. Another trick you can do if you have thick walls (thicker than 30mm) that cause this issue is to replace them with two parallel walls to produce the same width but they are thinner. I know, this is not that great either, but it may help in some cases. I promise we will get to this at some point.

[tamas_badics]

One related question: Would you be upset if we changed the algorithm in a future version and your upgraded model started to show slightly different areas than in the old version? Some of your rooms may even become redundant, or separate into two rooms depending on the topology. Rooms are an interesting feature in Revit :-).

[Keith_Wilkinson]

if you asked me what I'd like the Room Area calculation to do I tell you I'd like it to accurately calculate the room area.

I'll be honest, not being a programmer I clearly don't understand the problem or why there seems to be a need for a workaround within the core program to calculate this.

that aside however to answer your question it would depend on how big a difference we are talking about.  For example we would rarely show room areas to more than 2 decimal places when using m2.  If it was accurate to this degree I'd probably not worry too much.

I'd also like access to this value in any schedule that allows access to 'To/From Room' parameters.

[Taase]

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@tamas_badics wrote:
One related question: Would you be upset if we changed the algorithm in a future version and your upgraded model started to show slightly different areas than in the old version? Some of your rooms may even become redundant, or separate into two rooms depending on the topology. Rooms are an interesting feature in Revit :-).

---

Short version:

I would not be upset. I would always prefer the most accurate calculation.

Longer version:

I would prefer, the most accurate calculation, but also an easy workflow. But I also think it is important to know what "accurate" is. For us it would only be 2 decimals. All our areas are only shown with 0 decimals, but for calculations reasons, I would like to have 2 decimals, sins all our areas are synchronized to dRofus*.

If a more accurate calculation would make the program slower, I would definitely not prefer a more accurate calculation. At this point our hardware is pushed to the limits, and we have synchronizing’s with centrals that takes from 5-12 minutes. We are 40 people working on the project right now, so this is a big deal.

I don’t know if a new calculation method would affect the synchronizing time, but if it makes the program slower, it would still be the same answer.

If this was updated in a future Revit version, we always look at the pros and cons of upgrading the files to the next version. We usually do this the project changes design phase. We do this to avoid problems in the end of a design phase. So if the update would make changes to the project as you describe, it would not be a problem, sins this would happen in a beginning of a design phase, and would be a lot easier to handle.

Please ask if this don’t answer your question, or you need further explanation.

*dRofus is a planning and data management database, made for hospitals. It is a “must have” for projects here in Scandinavia. www.drofus.com

[tamas_badics · Accepted solution]

Thank you for the prompt answers to my question.

In general, room boundary calculations are very accurate in Revit.  Even using the earlier described shortcut, the calculated areas can be trusted.

Since rooms can come in an infinte variety of shapes, it is impossible to give an exact percent to the accuracy.

When you set your plan view to show rooms with their blue boundaries, the reported areas are calculated from those polygons and they are as accurate as the polygon is. When you see a problem with the boundary, (a small sharp corner is cut off, or like above a column causes some trouble, etc) then the reported are may not be exactly what you want.

The cases mentioned up here are (in my opinion) the exception and can be fixed by room separation lines or some other tweaks I wrote about yesterday.

That said, we are aware of the shortcomings of the current approach and do plan to address it in the future.

Happy designing 🙂

 Tamas