What do mechanical drawings show?

• A. Electrical circuits
• B. HVAC and/or plumbing system
• C. Structural beams
• D. Fire alarm system

Answer: (B)

Mechanical drawings show the building’s mechanical systems, mainly the HVAC and plumbing networks. They depict how ducts and diffusers route air, where air handling units, boilers, chillers, and pumps sit, and how piping for hot water, cold water, drainage, and related fixtures are laid out and sized. These drawings guide installation and coordination, showing equipment locations, clearances, and connections to other building systems. They’re different from electrical diagrams (circuits and devices), structural drawings (beams and framing), and fire alarm/system life-safety drawings, which cover other disciplines.