Surveying
Control Point
A surveyed point of known horizontal and/or vertical position used as a reference for layout and measurement throughout the project.
🏗️
In the Field
Control points are set by the project surveyor and must be protected throughout construction. They are referenced by all trades for layout. On large projects, a network of control points is established and adjusted to minimize accumulated error.
📐
Rule of Thumb
Protect control points with lath, stakes, and paint. Put an orange flag on them. The cost of re-establishing a disturbed control point — survey time plus potential rework — far exceeds the cost of protecting it.