What do dashed lines on blueprints indicate?

Dashed lines on blueprints are commonly used to represent hidden objects or elements that are not directly visible in the plan view. This includes parts of the building or site that are located behind walls, under flooring, or otherwise obscured from sight. Using dashed lines helps to differentiate these hidden elements from those that are visible, providing a clearer understanding of the full scope of the design. For example, dashed lines may indicate features such as piping, ductwork, or structural elements that are concealed. Understanding this convention is crucial for interpreting blueprints accurately, making it easier for builders and contractors to visualize the complete design and plan their work accordingly.