Section lines of a drawing that show the material of construction are usually drawn at what angle?

Section lines in architectural and engineering drawings serve to indicate the material of construction within a section view. The convention for drawing these lines is to use a specific angle to ensure clarity and distinction between different materials. An angle of 45° is typically employed because it provides a good visual balance, making the section lines easily recognizable and ensuring that they do not clutter the drawing.

Using 45° lines allows for optimal contrast with other elements in the drawing, helping to maintain a clean and professional appearance while clearly conveying the necessary information about the materials used in the construction. This standard practice has become widely accepted to enhance the readability of technical drawings.