INSANELY FAST cw pipe modeling & sizing in Revit

I model an entire CW plumbing system in about 10 minutes
Get my free downloads and my Top 3 Secrets mini course at:
www.mepguy.com

[@mep_guy]

Get my FREE Plumbing in Revit mini-course: www.mepguy.com/

[@theelectricaldepartment]

Batch copy is so useful! We do this for Lighting fixtures a lot. Don’t forget to set your work set before you hit that copy button!

[@mep_guy]

Great advice!

[@ningzhou8397]

my background is not in MEP so my question may sound "stupid", your custom fixture have 2 connectors (horizontal and vertical) for the same purpose, convenient for modeling for sure, but only one will be used, and that unused one will always be there as unassigned in system browser, i believe connector is kind of special element in Revit, you cannot switch it via family type and/or visibility

[@mep_guy]

Yes, you are correct. what was your specific question?

[@ningzhou8397]

maybe redundant connectors won't cause big issue but still hope factory can make connector as 1st citizen (can swap via family type, visibility, etc.), i just noticed in your another video using multiple connectors for the same purpose like sanitary, just wonder if this will affect calculation?@@mep_guy

[@mep_guy]

@@ningzhou8397 It won't affect calculations in your piping, since the pipe sill only display flow associated with the connectors it's using. But you system browser will have some "unassigned" systems, which I just ignore.

[@ningzhou8397]

thanks Ryan, maybe i didn't make it clear, what i'm asking is the case that you used both (horizontals and/or verticals) connectors, so no "unassigned" systems but 2 connectors instead of 1, i believe you used this approach in your video, does this affect calculation? maybe i misunderstood it@@mep_guy

[@JulianTheOwl]

Ryan, Going through your plumbing 101 course on your site right now, and was wondering how you would size the water pipe for the lavatories given that it was assigning 15 GPM for the 1 fixture unit of a lavatory since the system type was set to predominantly flush valves. This video ostensibly answered that question, since after sizing for the water closets, you change the system type to predominantly flush valves before size the rest of the pipe. This method works for sizing the pipe, but thereafter you will not have an accurate GPM shown for your pipe, since the system type has to be set to either FV or FT. Without an accurate GPM, we don't get an accurate pressure loss calculation. Any thoughts on this?

[@mep_guy]

Are you talking about doing a pressure loss calc for the entire building?

[@Grenmaju666]

Bit of background: my Revit experience is in electrical, but I have recently become the BIM Manager for our MEP firm and am working on ways to improve the efficiency of both departments. I asked one of our MP engineers about auto-sizing and they say that auto-sizing nor auto-routing have ever been reliable for them. Is your success with it primarily attributed to your custom families or do you still need to go back and manually calculate your sizes and make significant adjustments to the auto-routing?

[@mep_guy]

Yea it only works if you understand how Revit calculations work. Revit uses fixture units and hunters curve per the IPC. Sometimes you have to use actual gpm instead of converting fixtures units to gpm. It's not complicated once you understand how it works. But my custom fixtures make it very easy since I've preset all the fixture units per the IPC. and I convert to gpm as needed.

[@cm20506]

How is the calculation made when the pressure of water entering the building is not known?

[@mep_guy]

Pipe calcs are based on flow rate. Flow rate is based on the GPM of the fixtures. Pressure has a negligible effect on the velocity of water through the fixtures so I can be ignored in the pipe size calcs. But it does matter it's just not how we size our piping. You could assume worse case the the pressure is 80 psi. GPM through all fixtures is a probability. We can't know the exact GPM at all times so we take a worst case based on the hunter curves.

[@royalsprite189]

question is there a automatic duct/pipe size in fire protection system as well?

[@mep_guy]

You can use it for any type of pipe. It will size your pipe based on the velocity or friction loss you set.

[@JWu-jt7fz]

But ideally your pipe sizing in fire protection should be based on your local fire code.

[@ajmalnattika9077]

How can i size the pipe with hot and cold and total (as per ipc standerd)

[@mep_guy]

I go over that in my course

[@rockybrown5013]

Hello, I am trying to buy your course online, but I am having issues. Unsure the best way to reach you. Any help would be greatly appreciated. Also, thanks for the content.

[@mep_guy]

Oh No! Thanks so much for reaching out. I will get this fixed immediately.

[@cm20506]

The critical path should take into account the pressure loss due to the "elevation difference". the pipes should have a new parameter indicating this pressure loss. Revit do not.

[@mep_guy]

When auto sizing you are assuming you have already have taken into account your head loss or pressure losses due to elevation. You size you piping based on velocity or friction loss. We still need to understand the fundamentals when using these tools inside Revit.

[@cm20506]

@@mep_guy Shouldn't Revit take this "elevation" issue into calculation? Isn't this a deficiency?

[@mep_guy]

@@cm20506 Not for sizing piping. When you are determining if the building needs a booster pump that's when you would take into account the elevation. Once you determine the need for a booster pump or not you work backwards from the pressure you have left over. You still need to verify your pipe losses don't exceed the extra pressure you have. Refer to appendix E in the IPC for a complete explanation of sizing piping.