A Plumber's Guide to BIM

 

The best thing since no-hub bands?

Back when I was a kid I remember my father saying, “I'm not putting a band-aid on cast iron pipe!” Times change. I know a lot of good plumbers these days who've never poured a lead joint, much less wiped a joint. The industry changes and our skills as craftsmen change.

BIM stands for Building Information Modeling. BIM is the next step beyond CAD drawings and 3D modeling. BIM adds layers of information and is sometimes called 5D design. In BIM all of the submittals, specs, and product data we printed up and put in binders for the architects, engineers, and owners are incorporated into a three dimensional representation of our work. But that's only four dimensions.

Time is the fifth dimension of BIM. The BIM model contains a realistic virtual installation of our piping systems, tagged with all of the information I mentioned, which we can use to extract material and labor calculations and cost estimates. In our BIM model we can bring together all of the information and data we use to bid the job, buy the job, install the work, and bill for our services. We can make accurate cost projections and realistic work schedules – then we can track progress along the way.

To do all of this we need a good, accurate model. Unfortunately the level of development in the industry has the MEP trades far behind the curve, and the plumbing industry is years behind Mechanical and Electrical. I work in Autodesk Revit and NavisWorks, but all the current design software available suffers the same limitations. In Revit the standard fittings are limited to tees and nineties.

Pipe can be sloped in Revit, but there aren't standard representations available of the wide range of pipe fittings used in the industry. You can add custom fittings to the program, but the program doesn't understand when to use them properly. The promise of quick material take-offs falls flat with a list of tees and nineties when what you need is a list of combinations, wyes, sweeps, quarter bends, eighth bends... And what about all those no-hub bands?

Mechanical and Plumbing Engineers design piping systems. They often leave the details of which fittings are used to meet code and create a properly working drainage system to plumbers in the field. If you are working with an architect and engineer who are using a 3D modeling program to design the building and a contractor who is using BIM to coordinate the work and provide documentation to the owner, you are likely to get a model with the standard tees and nineties that ship with the software, not an accurate representation of how you will install the plumbing system.

These powerful 3D models can tell you how many yards of concrete is in the building, how many feet of pipe you'll need, and in the case of water pipe how many tees and nineties are needed. (Though in the case of tees you will probably get a list of tees and reducers not reducing tees) In the coordination phase you can see if your pipes are conflicting with other trades, but as we know there is a big difference in the radius of a standard ninety or tee and that of a sweep or combination. And often that makes all the difference in tight spaces.

If your contract requires a realistic as-built model, with all the product data plugged in, you'll have a lot of work to do changing all those standard tees to combinations and sanitary tees. But it takes a plumber to pipe a building, even a virtual 3D representation of a building. This is where plumbers need to step up and claim the future. It should be the plumbers job to realistically pipe the model, not the engineer. You can go to manufacturer's websites, and in some cases supply house websites, to get all the add on content you need – from realistic fittings to exact 3D models of fixtures and trim – to use in your model.

Like the no-hub band, BIM will revolutionize the industry. Plumbers can embrace the new technology and leverage it for increased demand for our expertise and increased profits for our companies or we can ask the engineers to put our fittings in for us and we will just become robotic installers. BIM is here. Technology will become more and more integrated into the working environment. It is up to plumbers and the plumbing industry to use that technology to move our industry forward.