When it comes to plumbing CAD drawings services, the most commonly used software in the industry is AutoCAD, particularly AutoCAD MEP. It's widely adopted by plumbing designers, drafters, and engineers for its precision, industry-specific tools, and compatibility with other systems.

AutoCAD
AutoCAD MEP is tailored for mechanical, electrical, and plumbing professionals. It offers smart objects like pipes, fittings, valves, and fixtures that make plumbing design much faster and more accurate. Its 2D drafting capabilities are excellent for schematics, while its 3D features allow for basic system modeling.

Revit
That said, Revit is increasingly gaining popularity, especially in projects that follow BIM (Building Information Modeling) workflows. Revit allows users to create intelligent 3D models of plumbing systems with real-world data like flow rates, pressure, and pipe sizes. This makes it a better choice for large-scale, collaborative projects such as hospitals, commercial buildings, and infrastructure developments where coordination with other disciplines (like HVAC or structural) is essential.

Others
For those who prefer a more lightweight or specialized tool, software like SketchUp with MEP extensions, BricsCAD, or Magicad (for Revit and AutoCAD) may also be used, especially in Europe or niche sectors. However, these are less common globally.

Summary:

AutoCAD MEP: Most common for traditional plumbing CAD drawings, especially in 2D.

Revit: Preferred for BIM-based 3D plumbing design, suitable for collaboration and large projects.

Others: Tools like BricsCAD, SketchUp + extensions, or Magicad are niche alternatives.


Final Verdict: If you're looking for broad industry use and 2D drafting, AutoCAD MEP is the go-to. If your work involves BIM and complex projects, Revit is the smarter choice.