What does "T.O." signify in construction terminology?

In construction terminology, "T.O." signifies "Top of." This abbreviation is commonly used in architectural and engineering drawings to indicate the highest point of a particular element, such as a wall, foundation, or floor. It helps communicate crucial information about elevations, ensuring that all components of a structure align correctly in relation to one another. For instance, a drawing may specify "T.O. Wall" to show where the top of a wall is intended to be, guiding builders in achieving precise heights as per design specifications. The systematic use of "T.O." in plans enhances clarity and consistency throughout the construction process.