SCARM - Simple Computer Aided Railway Modeller
AutoCAD MEP - AutoCAD MEP software helps you draft, design, and document building systems.
TrainCad - Freeware Microsoft Windows program for designing model railroad layouts using standard tracks.
DataCAD - DataCAD is a computer-aided design and drafting software for 2D and 3D architectural design and drafting
AnyRail - AnyRail makes model railroad design so easy, it's fun!
AutoCAD Plant 3D - AutoCAD Plant 3D is a BIM software that lets you create, modify, and manage schematic piping and instrumentation diagrams.