What is the main purpose of using layers in CAD for MEP drawings?

Using layers in CAD for MEP (Mechanical, Electrical, and Plumbing) drawings primarily serves the functional purpose of facilitating easier modifications and visibility management. Each layer can represent different systems or components, such as electrical circuits, plumbing lines, or mechanical ducts. By organizing information this way, it allows engineers and designers to isolate specific elements of the design for review, editing, or analysis without the distraction of other systems.

For instance, if a modification is required in the plumbing system, the user can simply turn off the layers related to electrical and mechanical systems, making the editing process more streamlined and less error-prone. This organization also enables better collaboration, as different team members can work on separate layers simultaneously without interference.

The other options do not capture the true functional advantages that layering provides in CAD for MEP drawings. While aesthetic appeal is important, it is secondary to functionality in engineering practices. Combining all systems into a single layer would negate the benefits of organization and management of visibility, and creating backups is a separate process from layering that typically involves saving or archiving work, not the structure of the drawings themselves.