Construction Staking: Tools, Techniques, and Best Practices
Introduction to Construction Staking
Staking, in general, is the process of determining and marking the position an element should occupy in the field.
In the field of construction, this refers to marking and drawing on the work itself, at a natural scale, any building element defined in the project.
Instruments and Supplies for Construction Staking
These tools are grouped according to their function:
- Length measurement: measuring tape
- Verification of verticality: plumb bob
- Verification of horizontality: spirit level, water level, glass level
- Plotting of right angles: square
- Plotting of any angles: level telescope
- Plotting of alignments: pole, stake bed, rope tightener
The Measuring Tape
A measuring tape is typically made of plastic or metal, wrapped around a shaft enclosed in a box. Measurements are taken through a ring, with divisions marked in feet (often in red) and inches (often in black). Common lengths are 10, 25, 50, and 100 meters.
The Plumb Bob
A plumb bob consists of a heavy, pointed piece that hangs from a flexible coiled rope attached to a “nut” (similar to a pulley) that is the same width as the lower weight.
The Spirit Level
A spirit level features a glass tube, closed at both ends, with a slight convex curvature at the top. The tube is filled with a highly mobile liquid (alcohol, ether, benzene, etc.), leaving a small air bubble to indicate horizontal. The glass ampoule is encased in a metallic wire and mounted on a rule that underlies the instrument.
The Water Level
A water level operates on the principle of communicating vessels, using a transparent plastic tube (hose) filled with water. The water surface at each end defines the same horizontal plane. It is used to “pass level” from one point to another.
The Level Telescope
A level telescope consists of a telescope fitted with a spirit level and set on a foundation with three arms. The telescope can rotate around a vertical axis, with a graduated limb indicating the motion. The entire assembly is mounted on a telescopic tripod, allowing secure placement and adjustment to eye level. It establishes a visual horizontal in any direction.
The Square
A square consists of two rules (metal or wood) joined at right angles by another cross. It is used to draw a perpendicular alignment to another. A tape can also be used as a square by forming a right triangle with sides of 3, 4, and 5 meters (or multiples thereof), based on the Pythagorean theorem: h2 = a2 + b2, e.g., 52 = 32 + 42.
The Milestone (Stake Pole)
A milestone is a cylindrical rod of wood or metal, typically 1.50 to 2 meters in length and 3 to 4 cm in diameter, divided into alternating red and white strips for greater visibility.
The Stake
A stake is a piece of wood, generally prismatic with a square base and a pointed lower end to allow penetration into the ground when hit with a mallet. It is used to mark the goals of the foundation and can be secured with rope to a nail in the top or side.
The Stake Bed
A stake bed consists of a table longer than the width of the trench, secured by stakes nailed to the ground. The upper surface, which should be as horizontal as possible, is marked with a pencil or nail to indicate the position and edges of the foundation element. Stake beds are placed away from the edge of the trench to prevent collapse.
The Rope Tightener
A rope tightener is a fine line of hemp or nylon that, when attached to stakes and pallets, is used to define alignments.
The Laser Level
A laser level consists of a turntable that emits a laser beam.
The Total Station
A total station is a theodolite that emits lasers to a triangular element, which returns the signal to the device. It provides changing altimetric and planimetric measurements of the point.