Revit MEP and Troublesome P-traps
This blog post was originally written for the Managed Design blog. Managed Design is now a U.S. CAD company, so please check back here at www.uscad.com/blog for more written articles from Philip Charlson and our new U.S. CAD Minnesota team.
Revit MEP has been around for quite a few years now, but Autodesk has still not discovered a great way to attach a P-trap to the different plumbing fixtures you want in your projects. If you have tried placing one of these P-traps, you find that it typically faces the wrong direction, and sometimes, doesn’t connect to a pipe at all.
I recently found an easier way to add these P-traps to your systems so that they display correctly when you create your plumbing isometrics. In the picture below, you will notice a typical issue when you connect your plumbing fixture to the waste line.
Locate your p-trap family (OTB version) Trap P – PVC – Sch 40 – DWV.rfa and open the file separate from your project.
After loading the p-trap file you can access your Properties Palette, and within the palette, you will notice a parameter called Part Type. This will be listed as MultiPort. This enables it to be used in a number of locations, but typically for end conditions. Instead of keeping it set this way, we can set it to be a more specific component. In this case, we can set it as an Elbow. This will not change the look of your p-trap.
After making this change, I would suggest saving this p-trap in a company custom library for future releases, and sharing with your co-workers. You should also insert it into your company template for upcoming projects.
To start using the updated p-trap, locate elbows that have been placed within a project under your fixtures and select them. You can do a multi-select if you choose (don’t select all in the project though).
Within the Type Selector you will find all the other elbows along with the p-trap that you just modified. If you select the p-trap from the selector it will automatically replace the elbow in the project and orient it correctly without any hassle.
Even though it isn’t quite an automatic setting to just simply sketch the piping and have it place the p-trap as you’re designing – it does beat having to place each one manually and orienting it correctly for every instance in your project. As a bonus your plumbing isometrics will come out looking correct as well.