What include all information needed to fabricate and install a duct run?

• A. Architectural drawings
• B. Electrical drawings
• C. Structural drawings
• D. Mechanical drawings

Answer: (D)

Focusing on what’s needed to fabricate and install a duct run, you need detailed information about the duct system itself—its routing, sizes, materials, fittings, supports, insulation, and how it ties into equipment and controls. That level of detail is found in mechanical drawings. They lay out the duct layout, cross-sections or shapes, exact sizes, gauge or wall thickness, seam type, insulation specifics, and all fittings like elbows, transitions, and dampers. They also show how ducts are supported and hung, the spacing and attachment details, and where access panels or inspection doors go. Importantly, they specify connections to air handling units, fans, diffusers, and control devices, along with any fire or smoke damper requirements and required clearances. The mechanical drawings coordinate with other trades to ensure everything fits in the building and complies with codes.

Architectural drawings show space layout and dimensions but don’t provide the duct fabrication details. Electrical drawings cover power supply and control wiring for the system, while structural drawings focus on the building’s supports and do not include duct fabrication specifics. That’s why the mechanical drawings contain all information needed to fabricate and install a duct run.