Need general help with plumbing plans

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Did hundreds of plumbing and sewage plans, but even after switching to Revit continued to do them in Autocad. Now trying to go full Revit and a couple of things keep tripping me up.

I don't know how it's done in the States, but in my part of the world water pipes are, generally, run in the walls, hot and cold water one above the other. The wall is chiseled(?), and the pipes placed inside. Like this:

As a result our plans for plumbing are quite schematic. We just draw the pipes in space, next to each other. Like this:

I watched tutorials, I know how to draw pipes, set routing preferences... But actually getting a decent plan is a huge chore. I either have to place new fixtures moved away from walls, or place connectors and move them away, to get the pipes drawn outside of walls.
I also tried placing them inside walls. But since I have to draw them next to each other this creates all sorts of clashes, naturally.

So my first question is what would be the correct workflow to get, either plans to look the way they are done here, or to place pipes as they are actually placed but have them somehow both display?

My second question is regarding graphical display of pipes. As you can se in screenshot above, the pipes above "overshadows" those below with a white "halo", any way to remove it?

EDIT: set "Show hidden lines" in view properties to none.

Also, as seen below, in hidden view fixtures hide pipes. Why, how to fix? Do you create plumbing plans in wireframe?

Fourth question is about tagging. If the pipe is of the same diameter we often tag the length of the entire "stretch" of the pipe, no matter how many fixtures are on it (see the 240cm hot one and 490cm cold one on screenshot bellow). As far as I can tell this can't be done with a tag in Revit, right?

Last question is about piping systems. If I never plan on using automatic routing that Revit comes up with (because it's 100% useless) I don't even have to bother with creating systems, correct?

Oh, and one final question to European colleagues, do you use Revit for pressure drop calculation or do you do it outside of Revit, how ever you did it before? We have to use Joseph Brix method, but as far as I can tell that's not possible in Revit.

[HVAC-Novice]

I'm new to plumbing... but here some thoughts:

- model it the way it is built: fixture families usually have their connectors where the wall will be. And architects will hate you if your pipes show in front of the wall.

- use addl. 3D, section and other views if the plan view isn't great. those also help modeling

- with visibility you have to play a bit around to find a result that works for you. I assume you use filters for cold/hot etc. 

- If you have clashes in Revit, you also will have them in real life. 

- Tags can have multiple leaders and as long as those point to the same size pipe, it should work. 

- Probably a good idea to use the systems instead of Revit having to create too many. that's also how fixture units add up etc. (not sure if your code uses those)

- Multiple codes will calculate differently, but often come up with similar results. Try out if what Revit does comes close enough to your method. 

You didn't ask about this: I noticed many plumbing tutorials lay out sanitary piping WITHOUT slope, even over longer distances. I assume they know what they are doing and have some other way to not run out of elevation.... but IMHO, the slope should be modelled as actually required. This again a case that, if in doubt, model it as it will be installed. 

(One exception: Some trap families have an issue with 1/4"  over 12" and in those cases on short runs I use 1/8" over 12" until Revit can make the connectors be more flexible)

[RSomppi]

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@blank... wrote:

Last question is about piping systems. If I never plan on using automatic routing that Revit comes up with (because it's 100% useless) I don't even have to bother with creating systems, correct?

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Routing preferences are only useless until you set it up to your desired standards.

Systems are 100% necessary if you plan on doing calculations, among other things.

[robert2JCCH]

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@blank... wrote:

So my first question is what would be the correct workflow to get, either plans to look the way they are done here, or to place pipes as they are actually placed but have them somehow both display?

Fourth question is about tagging. If the pipe is of the same diameter we often tag the length of the entire "stretch" of the pipe, no matter how many fixtures are on it (see the 240cm hot one and 490cm cold one on screenshot bellow). As far as I can tell this can't be done with a tag in Revit, right?

Last question is about piping systems. If I never plan on using automatic routing that Revit comes up with (because it's 100% useless) I don't even have to bother with creating systems, correct?

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• Model as installed, or as close as you can manage with your families and agreed-upon level of detail. For the sake of sanity, we usually choose the route of 'more is more' - if it's modelled well, you should be able to capture the model from various view states (sections, 3D, floor plan), and supplement with annotations for a readable set of documents.
  The schematic representation on a floor plan in CAD is what I've heard called 'offset for clarity'. If that is something you want available in your plan representations, you can use the Displace Elements tool under Modify tab to isolate specific stacked branches and pull them away for visibility... it's not a perfect tool (you have to add/adjust the selected elements if you change the local pipe network in any way), but it does a decent approximation of the CAD workflow.
• I don't believe this is possible with Tee junctions, only Tap junctions. You'll have to get used to annotating each section if you're required to have a length value represented. For visibility we typically have these annotations on an enlarged plan or in the Isometric/3D plan views.
• Systems have value beyond the routing preferences tool, and you'll find that Revit will automatically generate systems as you connect fixtures and piping, even if you don't actively manage the System naming. While you get used to the plumbing component of the Revit engine, I'd recommend keeping up with the practice, as pipe network calculations and system disconnections/splits/incompatibility can be an accumulating source of lag as you work on the model.

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@HVAC-Novice 

@robert2JCCH 

- use addl. 3D

- you should be able to capture the model from various view states (sections, 3D, floor plan)

Yes, I was also thinking of additional 3D views as the best solution, since placing pipes in open space as in Autocad completely defeats the purpose of BIM (pipes placed where they wont be placed and collisions with other pipes and disciplines unusable). But it's really hard to be "the guy that changes things", especially when everybody else does it another way, and that way is how everyone in the industry is doing it, and the way that's been done since for ever. I can just imagine contractors when they look at a plan and see a hot water pipe seemingly connecting to a cold water pipe.

I'll have to run this with the powers at be, make everyone in the company do it the "new" way.

- You didn't ask about this: I noticed many plumbing tutorials lay out sanitary piping WITHOUT slope

No way, have to model it with slopes, no point doing it differently, I can stay on CAD if I'll skip that part.

- Systems have value beyond the routing preferences tool, and you'll find that Revit will automatically generate systems as you connect fixtures and piping, even if you don't actively manage the System naming.

Yes, already noticed it, ended up with four sanitary systems on a simple family home. So, even though I'm not using automatic routing or Revit flow calculations, best practice would be to create systems and manually draw pipes, right?

@RSomppi 

- Routing preferences are only useless until you set it up to your desired standards.

Would love if it could be done automatically! But I've watched a ton of tutorials and in none of them did I see anything even remotely close to how things are done over here.

For example, this is how cold/hot water is done:

Revit would offer five or six solutions, and they would all be something like this. I haven't seen any tutorials about how to set up system automatic routing for a more usable result. Can that be done?

[RSomppi]

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@RSomppi 

- Routing preferences are only useless until you set it up to your desired standards.

Would love if it could be done automatically! But I've watched a ton of tutorials and in none of them did I see anything even remotely close to how things are done over here.

For example, this is how cold/hot water is done:

Revit would offer five or six solutions, and they would all be something like this. I haven't seen any tutorials about how to set up system automatic routing for a more usable result. Can that be done?

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I misunderstood you when I responded. There is a difference between routing preferences and auto-routing and I was talking about routing preferences. I personally don't care for auto-routing but it is useful for some things. Routing preferences are always in use. It cannot be avoided. 

[HVAC-Novice]

Hope you have success to be allowed the newer (better) way. More views, colors etc. make it more readable for all parties. Obviously, if you ask 10 contractors, you get 15 answers what they prefer plus the ones that never want to change anything ever. 

The auto-routing can give results no plumber would use. Your piping in clay-tile is not much different of what we do in drywall or CMU. You can use the Revit auto routing and edit it, or just run pipes manually. Sounds like you have been a plumbing designer for a while, so you properly have an idea what works in the field. The circulation loop also may change how you actually want to  run pipes. 

this guy uses auto-routing a lot and you can learn some tricks (and amend them to what you need). 

[robert2JCCH]

Revit's auto-routing tool does not factor in model obstructions, so it's generally not practical for pipe system design. I've generally used it as a method to create 45 degree elevation offsets in situations where I didn't want to create throwaway sections, but that's a limited use case that has more to do with personal workflow than anything else.

There have been efforts made to improve routing optimization via generative design methods, but I can't say with confidence that they produce time-saving results versus a seasoned designer's natural shape/pattern recognition.

You will almost always receive friction regarding things looking different and not matching prior standards, and you've already hit the nail on the head that it's the difference between schematic intent and modelled intent. The tipping point when I was at this stage in a company transition effort was the following conversation (paraphrased):

CAD: "You can't read the plans like this, it looks nicer the way we do it right now."

BIM: "There's all of these installation notes on the side of the floor plan about pipe sizes and rise/drops, is that typical?"
CAD: "Yeah, it clears up the floor plan."

BIM: "How does the contractor know how to install the piping in this gang restroom stack and manage all of the pipe offsets?"

CAD: "Well we have an iso plan that shows it in more detail, where all stop valves and balancing valves go, etc.."

BIM: "The AHJ usually also requires one?"

CAD: "Yes, the model codes allow them to reserve that right."

BIM: "And that takes you...an extra work day or so to replicate information onto isos depending on the project size?"

CAD: "Depends on the designer for that project but yes."
BIM: "And the isos take priority in terms of portraying design intent"

CAD: "...yes?"

BIM: "So if the isos matter the most, and you have to do them anyway... if I start by modelling the iso and it just so happens to spit out a floor plan simultaneously, that means you're only drafting this design once per iteration, instead of in two locations per iteration?"

This got into additional conversations where the realization was that, most of the time, general floor plans existed simply to convey how piping got from one part of the building to the other, and enlarged plans/isometrics generally contained the bulk of the detailing/annotating effort as to what the piping did once they got into the rooms containing fixtures. Once that observation was made, it was a lot easier making the argument to transition over, since you gained time via single-source modelling and actually didn't lose too much in terms of design clarity.

[blank...]

Thanks guys, some things are clearer now.

Regarding systems, I know they're "a set of logically connected elements", but how do you generally approach creating them. Our scope of work ranges from small family homes to ~6 floors apartment buildings (20-40 apartments).

For family homes it seems logical to put everything on one system.

But what about bigger buildings? I'm thinking everything that goes in the same sewage stack is one system, since it's not uncommon to have ~10 stacks in those buildings.

On the other hand, cold water often gets routed to all floors with just one vertical pipe, usually in the stairway corridor since we have to have water meters on every floor for every apartment.

So whole building is one cold water system?

[HVAC-Novice]

So much this. Over the last 12-15 years I have been trying to convince people to use Revit. The people who don't want to use BIM are usually in these groups:

- principals who don't actually design themselves and rely on what their drafters tell them (and some of them later admitted they should not have listened to drafters)

- CAD drafters who don't want or or can't learn something new and are afraid to lose their job

- Designers who aren't really great with CAD, but have even less confidence to learn something more complex. 

Basically all people who never used Revit in earnest, have enough confidence to claim it isn't suitable. 

I haven't met a single person who used Revit for a while and has the cognitive ability to "figure things out", that would want to go back to AutoCAD. 

[robert2JCCH]

If you model well-connected fixtures and piping, ignoring the systems tool, and then come back to the systems browser at the end of the design, you'll find that your number of naturally generated systems winds up being one system per physically-connected pipe network. So if you have two sanitary laterals leaving the building, you'll wind up only having two sanitary systems in the project.

This is, usually, fine. It can become not fine in significantly large projects, because Revit will constantly attempt to update network calculations (critical path, flow rates, etc.) as you manipulate piping. So if your pipe network is several thousand pipes, elbows, tees, wyes, etc... it can start to hamper performance. At that point it might be prudent to break either the model up into smaller models, or break the systems up into smaller systems, so that network calculations don't impose a loss of productivity. I've only experienced this sort of situation in multifamily multifloor projects.

For smaller projects than that, I actually use the existence of multiple systems in one type (like multiple generated sanitary systems) as a diagnostic tool, since that likely means there's a significant systems disconnect occurring somewhere in the project. At which point I turn on the pipe disconnects warnings tool, turn on pipe system analysis, and start checking if there's a badly created family or improperly connected stack somewhere.

If you use Systems as part of your actual project documentation (like having a schedule with flow rates or take-offs), you'll want to pay much closer attention than what I'm describing above.