topic Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models? in Revit MEP Forum

Should you develop more than ONE Model for MEP work? Or use Multiple Models?

Anonymous — Tue, 25 Apr 2017 22:23:26 GMT

Right now we typically use One Revit model for all of our MEP work. The question has come up, should we use multiple Revit models? One Revit model for plumbing, one model for mechanical and a model for electrical. What are the pros and cons of having multiple models? Why would anyone want to have multiple models as your level of coordination goes down and are not able to sync and save the other disciplines work? Just would like some feedback based on your experiences. Thank You.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

RobDraw — Tue, 25 Apr 2017 23:15:31 GMT

When multiple models are used, they are usually linked into each other. Coordination can still take place on the fly or with clash detection.

Is one model better than multiple models? There are a lot of factors that would determine the best choice.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

fabiosato — Tue, 25 Apr 2017 23:57:32 GMT

Hello,

We choose to model as separate files, because if the model goes big, we can unload the unnecessary files, to get it lighter.

Of course coordination is not so straightforward, it demands more communication, but as the company is small, 15 persons modelling, working all in the same room, it is OK.

Another aspect for us, was the demand for hardware, bigger models demands better computers and more memory.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

chris.kershaw — Wed, 26 Apr 2017 07:26:01 GMT

From a Coordination point of view id never dream of splitting services into separate models it just makes your job so much harder.

if say your in the plumbing model & need to move or set a duct you have to first open the vent model, move the duct, sync, then go back to your plumbing model to continue your pipe run. IMO thats just not an efficient way of working

as for file size Im working on a medium size project & the file size is around 600mb & yes sync times can be 5 mins but working is just fine. If working speeds are an issue then there are other more efficient ways to help this rather than splitting models. for multi story buildings create a workset for each floor. you can then chose to only open the floor your working on. if its low rise large footprint then you can split the areas into worksets & do the same.

If the size ever became a problem then id look at splitting the MEP model into zones/areas but never into separate M, E, P models

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

RobDraw — Wed, 26 Apr 2017 07:36:31 GMT

In my world, different people work on each the trades. Sometimes multiple people. Having separate models is actually beneficial for a number of reasons.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

kadmonkee — Wed, 26 Apr 2017 10:33:13 GMT

we have applied both methods.

it does vary based on size and scope of work, the size of the team etc.

it is a discussion that happens early on but needs to be flexible enough to accommodate many options.

location if multiple offices may have lags in service

I would prefer one model for MEPFP which leads to a more open and coordinated effort.

the down side to this would be anyone can move something that they do not own so accountability plays a role too.

good luck.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

RobDraw — Wed, 26 Apr 2017 11:27:27 GMT

@chris.kershaw wrote:

sync times can be 5 mins

That would kill us.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

geoff.black3UL8X — Wed, 26 Apr 2017 11:34:04 GMT

We are an Electrical Design and Installation Company that use various models supplied to us from our client, supplied from their various partners. We work on industrial sites which can be quite large and contain several buildings/areas of process. We break the site down into 2 or 3 areas and opt to create separate models for each. We only have a small team here, 3 people but it enables us to each work in an area without the need for Workspaces or constant sync'ing.

This works for our client as they too separate out the areas.

As all models are linked to shared co-ordinates, thus being able to create a federated model, the need or want for separate models should be based on the requirements of the work, the size of team you have and how easy it is to manage. The only other reason for separate models would be for design discipline reasons; Electrical, Plumbing etc. but if you have good processes in place and good work ethic from your team, turning this from and to various disciplines within one model shouldn't be an issue.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

Anonymous — Wed, 26 Apr 2017 13:32:51 GMT

Unless your building is huge I'd strongly recommend keeping all MEPT elements in a single model. Even then, I'd recommend splitting the building into separate models based on the layout of the building rather than separating disciplines.

When the disciplines are in separate models, you lose a large portion of the BIM functionality that Revit provides, because building systems can't be connected across separate models. This can be alleviated to a degree using the Copy/Monitor function, but I've found that method to be somewhat less than reliable. At best. Electrical is probably the discipline most hampered by using individual models for each discipline, but they'll all feel the same pain.

Also, using multiple models will increase the amount of time your project team spends on model maintenance and troubleshooting, because every single thing that goes wrong when the architects change things now needs to be repaired 3-4 times instead of one.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

stever66 — Wed, 26 Apr 2017 16:50:39 GMT

My vote is also for a single model, unless the file gets really large.

Actually, single model, separate worksets. I believe you can even unload other worksets if the model gets too large or slow.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

Anonymous — Wed, 26 Apr 2017 17:48:02 GMT

Actually, single model, separate worksets.

I'd recommend avoiding this method as well. Again, with the exception of much larger models. Worksets slow down model performance, sync and load times, and unless your entire team is very proficient with Revit, you will have dozens of items placed on incorrect worksets.

Basically, this is how I'd approach it:

-best practice is to keep all MEPT disciplines in a single model, and minimize the number of worksets in it. Try to keep it to Levels & Grids, Workset 1, Site, and maybe separate worksets for linked A & S models.

-At some point around 100MB, separating M/E/P/FP/T onto individual worksets might be worthwhile provided all users can be relied upon to use them properly.

-Once you approach 200MB, consider separating the model into two based on the building arrangement - if you can split it cleanly along a wing/building line/structural joint, that would be ideal.

-As an absolute last resort on truly gargantuan projects, it might be beneficial to have separate M/E/P/FP/T models. I've only done this once and it was a hot mess, and caused at least as many problems as it solved.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

RobDraw — Wed, 26 Apr 2017 18:18:25 GMT

As you are reading these comments, keep in mind that just because others have had difficulties with a particular workflow, others have used it successfully multiple times. There are too many factors to consider for anyone to say what is best practice and what shouldn't be done. Be speculative of anyone who says this or that shouldn't be done and this is the best way. There are reasons for alternatives and what suits one may not be appropriate for another and just because someone had a hard time with a particular method doesn't mean it is bad. It probably means it wasn't implemented correctly. Especially when the reasons for not doing it include user error. That doesn't mean it is a problem with the method, it's a problem with the users. Granted, the skill set of the users should be taken into consideration, but with good people, even methods that others have failed with will work.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

Anonymous — Wed, 26 Apr 2017 20:09:46 GMT

Thank you everyone who has responded. Unfortunately, our issue is not with space, but time. We do not seem to have enough time to react to all the engineers' markups to finish the project on time. So we are using an outside firm to help with some of our Revit. If we had separate models then this outside firm can do one discipline while we focus on the other disciplines. The main question is how to coordinate? I have told management about C4R, but I think they are on the fence about purchasing more software. The saga continues. Thank You to everyone who had opinions. I appreciated all your comments.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

RobDraw — Wed, 26 Apr 2017 20:40:09 GMT

Division of labor is a common reason for using multiple models. It works, despite the what the nay-sayers have to say about it.There are a number of ways to work with consultants and some don't require the models to be constantly linked. I've worked on plenty of large projects where we simply updated links on a regular basis. Ask for suggestions in another thread, though. I'll be looking for that topic.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

stever66 — Wed, 26 Apr 2017 22:09:37 GMT

We use Revit server to share the same central file between offices.

I'm honestly not sure how it works, or how our CAD people set it up, but it seems to work well.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

Scott_D_ — Wed, 26 Apr 2017 22:32:50 GMT

We have used Revit Server successfully in the same way you could currently be using it but C4R may now do what that does, not sure as I haven't used it.

I would always use one file for each building, I generally find that the people who complain about model size and speed are trying to run Revit on £300 laptops which is never going to end well.

To work better with engineers ask them to markup your sheets printed to DWFx files. These can be inserted into the project as an overlay onto your Sheets which makes revision changes a doddle and also gives you a history of every change made to every sheet, should you need it. It avoids the 'can't read the handwriting' issue and allows the Engineers to work at scale, measure and draw as well as click on a socket and see what circuit it is on and the power load etc which is very useful. What comment method are you using at the moment?

Revit Server costs pretty much nothing except a bit of space on your Server.

If your staff are not particularly experienced they may not be working in the most expedient manner. When you work with a lot of customised content you can make global changes that take a lot of the work out of the revision and documentation process.

Even simple things like using proper electrical system Tags rather than plain text for circuit references can save huge amounts of time and errors.

Is there anything in particular you are struggling with, we might be able to advise a better way of doing things. Depends what your doing of course!

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

Anonymous — Wed, 26 Apr 2017 23:11:12 GMT

This is an interesting topic. I was wondering what you would do when using a common MEP model and upon opening the model you receive the following message?

Having the other disciplines make these choices for my elements in the model causes me some hesitation. This is probably not likely to happen on a regular basis. I was just wondering how those of you working in a common model deal with issues such as this.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

jsgalve — Thu, 27 Apr 2017 03:25:15 GMT

Ours take around 30mins - 1hour (Revit Server) for a 700mb file size. From my experience Working on different models (Electrical and Mechanical) could bring you disaster. The main key to avoid this would be a fair share amount of Communication and Coordination. One needs to trust the other back and forth.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

Scott_D_ — Thu, 27 Apr 2017 08:41:14 GMT

Trav0 I generally only see that warning when the pipe fittings are too close together and something breaks.

The only option is to Delete the pipes and get the modeller to draws the pipes properly/again.

No software is perfect.

Re: Should you develop more than ONE Model for MEP work? Or use Multiple Models?

RobDraw — Thu, 27 Apr 2017 11:02:47 GMT

@jsgalve wrote:

From my experience Working on different models (Electrical and Mechanical) could bring you disaster.

Nothing could be further from the truth. I'm sure it has nothing to do with separate models. In fact, having separate models has saved us from losing hours of work on more than one occasion when users caused problems or system crashes. Yeah, we lost work but only in those models. The other models were untouched by the incidents. If we were using one model for all trades, many hours of work would have been lost.

Chew on that for a bit and think about it before spreading false information.