topic Re: Handling drainage/vent piping and view ranges in Revit MEP Forum

Handling drainage/vent piping and view ranges

micphillips — Tue, 16 Apr 2024 16:09:08 GMT

I'm trying to figure out what the most practical way to handle sanitary, storm, and vent piping in Revit. I want to improve my strategy to something more practical and I'm curious what other people do.

This is how I currently handle drainage plans; I have one single view for each level that shows all sanitary, storm, and vent piping. I slope all piping to make sure fall is coordinated with architecture and structure. For a multistory building, we show sanitary and vent piping serving fixtures on the first floor, on the first floor plan. So our view range is a couple feet below level up to a couple feet below the level above, so under slab sanitary is visible and we don't see second floor under slab sanitary piping on the first floor. For storm piping, we like to handle that as if the cut plans were floor to floor.

Assuming the above makes sense to anybody other than just me, this presents a few problems:

Depending on how the architects setup their model, it can sometimes be difficult to show walls correctly. For instance, sometimes it's difficult to not see the walls on the floor below due to the cut plan being below the floor. Usually it's possible to override the architect's model with a view from their model, but that's not always the case.
Since the top cut plan has to be a couple feet below the floor above (so we don't see sanitary serving the floor above), areas where there's very little space and sanitary serving the floor above and vent serving the floor in question are so close that it's difficult to make sure things display on the level they are supposed to display. This leads us to have to show vent piping lower than it will actually be installed.
Storm has a similar situation. Since we show storm piping as if there were no cut planes, we often have to show it lower than it will actually be installed so it shows on the correct levels. With it being sloped piping, it often falls below the ceilings in some areas, even though it will all be installed above the ceilings.

9 times out of 10, these are non-issues because the plans look fine. The problem arises in situations like what we are dealing with right now where architects have RCPs and can see our piping below their ceilings. They don't want to just turn the piping off because they do need to see the drops in walls and chases.

I know how I'm handling this right now cannot be the most practical way to do things. This is just the way I was taught many years ago. So my question is, what does everybody else do? Do people have similar issues? Is there some sort of industry standard I'm unaware of? I would love any insight people can give and if anything I said doesn't make sense, let me know and I'll try to elaborate.

Re: Handling drainage/vent piping and view ranges

iainsavage — Tue, 16 Apr 2024 17:19:32 GMT

"sometimes it's difficult to not see the walls on the floor below due to the cut plan being below the floor"

Do you really mean the cut plane or do you mean the bottom plane or view depth?

In MEP views the cut plane does not affect MEP elements so you can set it at something like 1200mm or 4 feet which will usually cut doors and windows on your reference level without affecting display of MEP elements above or below that plane.

If your talking about walls on the level below that are within your view range then you should be able to use a view filter to exclude them, based on their top/bottom constraints

No filter:

With filter:

"Since the top cut plan has to be a couple feet below the floor above (so we don't see sanitary serving the floor above),"

Again you can use view filters to exclude certain elements. You can filter pipes based on elevation and you can filter fittings an accessories based on reference level.

BUT

"it's difficult to make sure things display on the level they are supposed to display. This leads us to have to show vent piping lower than it will actually be installed."

Fundamentally you should model elements in the positions in which they will be installed. This is 3D modelling not drawing/draughting. The model is supposed to be a "digital twin" of the real-life building. Putting elements in the wrong place will also mess up coordination checks and clash detection etc.

Also would the installing contractor not want to see everything which is going to be in the ceiling void, rather than having to refer to one sheet for some of the items and another sheet for the rest of the story?

"Since we show storm piping as if there were no cut planes, we often have to show it lower than it will actually be installed so it shows on the correct levels. With it being sloped piping, it often falls below the ceilings in some areas, even though it will all be installed above the ceilings."

See previous answer - you shouldn't model it that way. Model it accurately then find ways to display it as you want to see it.

View filters are the essential tool for you to achieve the look that you want without corrupting accuracy of the 3D model.

Re: Handling drainage/vent piping and view ranges

fabiosato — Wed, 17 Apr 2024 22:37:50 GMT

Hello,

Another setting you can try on the Revit link tab in visibility/graphics overrides is to use a linked view from the architecture model.

It will use the architect's view range instead of the one from your view.

Re: Handling drainage/vent piping and view ranges

iainsavage — Wed, 17 Apr 2024 22:45:54 GMT

Thanks.

@micphillips said though "Usually it's possible to override the architect's model with a view from their model, but that's not always the case" so I was trying to give them other methods.

Re: Handling drainage/vent piping and view ranges

RLY_15 — Mon, 22 Apr 2024 23:24:03 GMT

I've seen two approaches locally for DWV/Storm plans:

View Ranges match architectural fixture placement/narrative by spanning from below the floor to capture the sanitary/storm horizontal, then up until above the flood rim/vent stack connections, and that defines a floor view.
View Ranges match structural plans by being defined as explicitly level-to-level, with a 'Foundation Plan' capturing the first floor sub-slab horizontals.

Both work and should be internally consistent, but you have to make it explicit on a cover sheet or similar how the drawings need to be interpreted.

The bigger issue that I'm seeing you note is that architects see piping in RCP plans but want to retain stack visibility - I can't say that's something I see often. Pipe rise/drop symbols get less intuitive on RCPs, and plan regions on RCPs simply do not work with MEP elements https://www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/In-Revit-RCP-views-duct-is-not-visible-inside-plan-regions.html . Unless there's a logical reason to try and see vertical piping on a ceiling plan, I wouldn't recommend it. And if it's necessary, implement filters to prune out the non-stacked piping instead of compensating by physically moving piping. The model serves as the design intent, and the view/sheets the explanatory material. Either modify the view settings so that the intent is captured better, or supplement with additional views (sections, isometrics) to portray what isn't readily understandable in the plan/ceiling view.

Re: Handling drainage/vent piping and view ranges

micphillips — Thu, 25 Apr 2024 17:52:26 GMT

Thank you so much. This all makes sense. As for creating a filter to display/hide the piping, I'm really struggling. I

m currently working in Revit 2024 and there doesn't seem to be an Envert Elevation parameter that works based on the project base point like in the past. The invert elevations associated with piping are all based on the pipe's reference level, but you can't filter piping based on reference level.

So what I'm struggling with now is, let's say I have sanitary piping below the first floor and below the second floor. On the first floor plan, I want to see the sanitary piping under the first floor and NOT the sanitary piping under the second floor. But, I need the view range to extend up to the second floor so I can see vent/storm piping as well. I'm trying to create a filter to hide the sanitary piping under the second floor. Since you can't filter based on reference level and there's no project base point invert elevation parameter, I don't know where to start to create this filter. I've been spinning my wheels for a couple of hours now trying to figure this out.

Re: Handling drainage/vent piping and view ranges

iainsavage — Thu, 25 Apr 2024 20:08:01 GMT

Hmmm.

I hadn't actually done this for a while and it used to be possible in older versions using Invert Elevation for pipes and Level and Elevation from Level for fittings and accessories.

Invert was an absolute value so you had to have a series of filters, one for each level, but that was easily achievable unless you had many levels in the building.

As you say though what they have now done (version 2023 onward) is allowed filtering by (relative) elevations but without providing the ability to filter by reference level, so that doesn't work.

Apologies for misleading you.

BUT

Personally I wouldn't organise the sheets that way in Revit.

I would have, just by adjusting view ranges, a sheet showing the slice from just below ceiling on level 2 to just below ceiling on level 1. You could if you want separate out Sanitary pipe and Vent pipe but basically anyone looking at the view would see the complete picture of the pipework in that slice.

Then do the same on the level above showing just below ceiling on level 3 to just below ceiling on level 2. etc etc.

Also show some sections and maybe 3D snapshots.

I think that would be more illustrative for coordination purposes.

Again, you need to reconsider how you used to show stuff in 2D in Autocad using some "draughtsman's licence" versus how to visualise and present an accurately modelled "digital twin" 3D model.

Re: Handling drainage/vent piping and view ranges

micphillips — Fri, 26 Apr 2024 13:55:23 GMT

Thanks. We certainly don't want to change the way we display drawings in our office because of this. So, I guess what I'll do is just create two views to overlay on each sheet. One that shows the underfloor sanitary piping up to above the fixture traps and another view to display the above floor vent and storm piping.

Re: Handling drainage/vent piping and view ranges

iainsavage — Fri, 26 Apr 2024 15:55:00 GMT

I was having another think about this and there is maybe another solution.

The method currently falls down because you can't use the pipe reference level in a filter BUT you should be able to transfer the value of that parameter to another shared parameter and then you should be able to filter by that parameter plus the elevation from level.

Dynamo can extract the values from the built in level parameter and pass it to your own shared parameter.

I haven't tried this but I'm pretty sure it will work.

Re: Handling drainage/vent piping and view ranges

RLY_15 — Fri, 26 Apr 2024 16:39:01 GMT

It would work. You'd grab the Reference Level, convert the name to a String, and push the String into a parameter intended for filtering purposes.

It just requires good modelling practice be upheld - things go awry if you start mixing and matching Reference Levels while working on floors.

You also need to check how the display of vertical stacks through levels are associated - if a stack spans uninterrupted across 2-3 levels, what are you assigning it to? You may wind up needing to split pipe at Levels to maintain visibility on both 'sides'.

Re: Handling drainage/vent piping and view ranges

iainsavage — Fri, 26 Apr 2024 17:07:34 GMT

Did a quick trial and it seems to work.

Dynamo script attached.

Re: Handling drainage/vent piping and view ranges

micphillips — Mon, 29 Apr 2024 13:46:02 GMT

Thank you both for this! I was also thinking about creating a parameter, manually selecting piping in a 3D view, and entering the level of that piping, but this is much more efficient. We are just now starting a new 3 story school project, so I'll test this out and see if this is how we want to handle things going forward.

Re: Handling drainage/vent piping and view ranges

iainsavage — Mon, 29 Apr 2024 14:09:49 GMT

Good luck.

As @RLY_15 said you'll have to be disciplined about ensuring each pipe, fitting and accessory has the "correct" reference level for this to work.

Long term though I think you should re-consider how you present output from accurate 3D Revit models versus output from slightly more schematic drawings in Autocad.

Especially making more use of "effort-free" sections, 3D views etc.