Opinions on design process within Revit

[Ivan B]

Good morning. Yesterday I have had a chat with HVAC engineer working for one of the UK's biggest consultancies. Discussion was about revit implementation and preference of CAD versus Revit in M&E. According to him, Revit is a fine tool and clients love 3D part of it but:
1. Company gain no extra revenue from implenting 3D for M&E
2. It takes longer to produce model compared against CAD 2D design
3. Crucially, changes in Revit affect project systems wide and change of design takes time, more than they wanted it to be.
4. Contractors still use 2D, printed drawings and no contractor would go with an Ipad on site to refer to 3D model (whis comes mainly to the lack of skills and educations, technology is afterthought).
5. It is simply nice but unnecesary to have 3D.

Is this common perception of the design process and Revit in particular ?

[ghale]

There are plenty of truths in the statements made. What's happening is that we are addressing issues with the design and construction processes through the use of technology and better design practices. It may not be cheaper or faster for design, but it should be cheaper and faster overall, by avoiding issues in the field. This is the value proposition that they need to provide to clients and that's rarely easy in a competitive bid situation.

[Monkey With No Name]

There are plenty of truths in the statements made. What's happening is that we are addressing issues with the design and construction processes through the use of technology and better design practices. It may not be cheaper or faster for design, but it should be cheaper and faster overall, by avoiding issues in the field. This is the value proposition that they need to provide to clients and that's rarely easy in a competitive bid situation.

I think there are plenty of untruths in that statement too.

Initially, producing models does take longer than drawings in 2D, but after a few years of swearing, crying, mouse throwing, template development, we can produce drawings from Revit just as quick as we used to in 2D AutoCAD, but with the added benefit of accurate, coordinated sections, 3D views, etc. With the drawing quality & speed up to standard we are now focusing on scheduling etc. This is based on extensive collaboration between the CAD & design engineers, changing of workflows, accepting drawings will be different to if produced in a drawing program. Of course we still have issues we wouldn't have in AutoCAD, but it gets easier every day.

Obviously we supply our site guys with dimensioned up 2D prints but they love running round the site in Navisworks Freedom, and it only needs the guy in charge to understand how to use it, he will show the underlings how something fits together on site. Even if 3D models are not used, we add 3D views to the drawings to show complex areas. 3D views are not just flashy fluff to show the client.

Depending on complexity of the project & quality of draughtsperson, 3D might be a nice to have or have no added value at all. The biggest & most immediate value of Revit for us is still coordination, so D&B contractors will probably see the biggest benefits.

As for gaining no extra revenue, that seems particularly short sighted. Some clients now require the M&E in 3D and I assume that requirement will increase so the company may start losing revenue from not implementing 3D. That with producing drawings quicker & more accurately in theory the jobs will be more profitable with less time spent on them.

I think these statements have been thought of as true by everyone who has made the transition along with the thought "this is not worth it" but they were overcome and are now seeing the benefits. I believe there are plenty of large UK/multi-national consultants not only using but pushing Revit, so hearing other consultancies having no desire to overcome the barriers to Revit doesn't worry me. Eventually they will have to and they will be coming to people with the right skills & experience desperate for help.

[Ivan B]

Thank you very much for your answers!
I haven't got much experience with the industry and BIM in particular but Revit workflow is not too difficult to manipulate and change of the system component or other design elements are going to be quick and successful, if designer thinks end result.
On another note he has claimed Revit is not used much to make HVAC calculations due to the previously unreliable results and alternative software is used (IES etc), therefore another limitation comes into play.
Whilst reading job listings for Revit MEP, I have asked myself many times if Autocad proficiency is still a main selling point for anyone wishing to apply for a position?
I was going to focus only on 3D, with Revit/Navisworks and some other packages, but at this moment AutoCAD seems like the only bridging ticket to the full employment, considering requirements of job listings.

[Wanderer]

Thank you very much for your answers!
I haven't got much experience with the industry and BIM in particular but Revit workflow is not too difficult to manipulate and change of the system component or other design elements are going to be quick and successful, if designer thinks end result.
On another note he has claimed Revit is not used much to make HVAC calculations due to the previously unreliable results and alternative software is used (IES etc), therefore another limitation comes into play.
Whilst reading job listings for Revit MEP, I have asked myself many times if Autocad proficiency is still a main selling point for anyone wishing to apply for a position?
I was going to focus only on 3D, with Revit/Navisworks and some other packages, but at this moment AutoCAD seems like the only bridging ticket to the full employment, considering requirements of job listings.

I think there is a lot of potential for a revit person in the MEP industries, because most folks are so entrenched in their current ways. Locally, I certainly see a lot of demand for it.

I'm from the owner's side, and I just give a big old "I don't want your opinions on a few months of the project time, just give me what is specified in our contract specs, because that is what we need to maintain our facility and plan for the next 100 years." to those who say the effort isn't worth it.

(anyone who wants some light reading on post-occupancy BIM can start with the links on the Facilities Management Community page)

[david_peterson]

The main problem that I see is that most MEP firms in a design bid build contract, are only required to show design intent. That's all the get paid for. So they might model things, but really only look at certain areas of the building in detail. The contractor is still responsible for the Mean and Methods of how all the systems go together and where exactly they are located.
If you look at an IPD type process, the MEP engineer is going to be responsible for sizing duct runs and and such and the contractor is generally responsible for final location of diffuser as an example. With this method there's a lot of gain using revit since the contractor is producing the as-builts, the engineer really only need to size the duct and list the number of diffusers per room.
So I'd say it really all depends on your delivery method and the type of project. For example, coordinating where all the services go in a typical office building is a walk in the park for the most part. You really shouldn't have any problem fitting all the systems nicely in their place. Now take a look at a large Biological Research Facility where things need to be set up with triple redundancy. If you don't figure out where exactly everything goes, it's going to take twice as long to get built and you'll end up with a product that is different from the design. You'll have added bulk-heads, lower ceilings and ease of maintenance will be hindered. If you modeled everything to a LOD 300 so everything was in a correct place, the over all cost should be cheaper and you should have a better product in the end.
So I'd say if you're company is good at BIM, you should be able to sell that do the client, demand a higher fee and see less conflicts in the field, less change orders and less CB's. Of course this assumes that the entire design team is on board with putting forth the effort during the design phase.
I can tell you my last major project (still under construction) could never have been completed without the use of revit in the time frame that our client demanded. With the speed at which the project was being design it allowed our Architects, MEP and Process folks know where they needed to put thing since the structure was already being put up. We effectively took away the option of "Hey, can you move that beam? 1.4 million Sqft facility, Building was split in 3 packages, Foundation Package 1 was created and submitted for construction in 4 weeks, Steel Package 1 followed 8 weeks later with the foundation package 2 and prelim foundation 3.
When we were asked where a beam or footing was located, "Where ever it is in the model" was the typical response.

[Ivan B]

I am reading all topics about bim and collaboration and at the moment developing particular interest in data profile of revit parameters. Few questions coming into mind whilst analysing information:
1. What is the main metrics for design (efficiency) and BIM evaluation?
2. How do you benchmark (test) metrics and who do you benchmark against?
3. Are those metrics project dependent or they are industry/sector-wide and static?

[Brian Myers]

One of the issues with metrics and BIM is that while your deliverable may be contractually the same, your standard of care is not. This means that when you use BIM processes your quality of work ... when done properly... will be enhanced. The required level of professional due diligence will be achieved. That doesn't mean you can't do your job the "old way" or that in any way you are intentionally hurting your clients or professional reputation by doing things in a traditional fashion. But BIM DOES eliminate errors and it can reduce costs on an instance by instance basis. It also drives project teams to collaborate so that even if your discipline does not see a direct benefit on the project, some part of the project team usually will... thus the owner will benefit from an enhanced product by the time of project completion.

Thus your final metrics come from reduced RFI's, improved client relationships, enhanced marketing/business drivers, and an enhanced level of professional care. They are difficult things to put metric to. The best scenarios are when you match the numbers you have always achieved, but realize that you and your clients are getting a higher level of design/build excellence. It just takes time (often 2-3 years) to reach those goals across an organization.

[jgibbs694171]

Even for us Architects, the investment in BIM needs to be seen as just that, an investment toward greater production. BIM is by nature a much more complicated process. At first, if you compare learning Revit to experienced AutoCAD, you cannot justify the transition based on immediate productivity. This issue is compounded in the engineering fields by their use of 3rd party programs for calculations, but Revit continues to improve built in calculating, and 3rd party vendors are making their programs work with Revit. I know for me, once I learned Revit well, productivity skyrocketed. I now produce drawing sets in days rather than weeks. 3d modelling vastly improves consultant coordination and visual design feedback. ductwork no longer runs into beams. we do not yet offer our models as our deliverable, still just making pdf's, but even there, including 3d images vastly improves the contractor's, owner's, plan reviewer's ability to understand the design and you get fewer questions and fewer screw-ups in the field. For me, holding to 2d cad because of immediate requirements for profitability is completely short sighted. There's a reason Autodesk bought Revit. Even they know where the industry is going. we now require all of our engineering consultants to use Revit. if they can't, they don't get our business.

[C Mann]

Our company has gone with Revit for most of our design work. I cringe when I have to go back to AutoCad nowadays. We have a project that it was REQUIRED that 3D modelling be the norm. Our electrical foreman on the job also has quite the computer in his job trailer. He has stated that having the NavisWorks model has upped jobsite productivity quite a bit. Just in showing the electricians design intent has saved quite a bit of time versus interpreting the 2 D drawings. This will be the jobsite way of the future I believe.