Mechanical discipline is provided with tools for setting autoffiting preferences for both HVAC and Plumbing systems. These preferences are stored in an XML file, and used as you route the system. The standard placement settings preferences set interactively through dialog will be applied to all fittings during routing. The route when changes in direction, size, or shape will automatically adds respective fitting, e.g. elbow, transition/reducer or branches such as take-offs, taps, or tees will be taken from what are set through autofitting preferences. The Saved autofitting preferences remain valid for the current project. The default values however can be restored as required.