Site Set Out Flashcards
What is an offset line in construction set out?
A line that is set up parallel to the boundary line in a location closer to the building’s intended location.
Why is an offset line set up parallel to the boundary line?
To maintain a consistent relationship and distance from the boundary.
In what location relative to the intended building location is an offset line typically placed?
Closer to the building’s intended location.
Give one reason why an offset line might be used during site set out.
When the boundary line is a great distance from the building location.
What type of site condition might necessitate the use of an offset line?
Obstructions preventing the boundary line from being pulled straight through.
If the boundary line is far from the building, why is an offset line helpful?
It provides a more practical and accessible reference closer to the work area.
How do obstructions on a site influence the decision to use an offset line?
They make it difficult or impossible to directly use the boundary line for setting out.
What is the primary benefit of using an offset line when the boundary is obstructed?
It allows for accurate setting out despite the obstruction.
What is a datum in the context of construction levels?
A fixed, known, and permanent reference point used as a basis for measuring all elevations.
What are the three key characteristics of a datum mentioned in the text?
Fixed, known, and permanent.
What serves as the “zero point” for the vertical scale of a build?
The datum.
What does RL stand for in construction?
Reduced Level.
How is the Reduced Level (RL) defined?
The height of a specific point on the construction site relative to the datum.
What is the relationship between RL and the datum?
RL is the vertical distance (above or below) measured from the datum.
What does the numerical value of an RL represent?
The vertical distance of a point above or below the datum point.
Give one example of a specific point in a build where the RL might be set.
The finished floor level (FFL).
Name two other examples of points where an RL is typically specified.
Foundation height, a point on a retaining wall.
Is the datum itself a numerical height value?
No, the datum is the zero point for the vertical scale.
On what type of consented drawings is the datum usually indicated?
The site plan or typographical survey.
Name one specific drawing where you would likely find the project datum.
Site plan.
What are some examples of physical features that can be used as a datum on or adjacent to a site?
Manhole covers, a steel pin embedded in a footpath.
Name one specific man-made feature mentioned that can serve as a datum.
Manhole cover.
Describe the appearance of a steel pin embedded in a footpath that might be used as a datum.
Usually a metal disc found in the ground.
What is another common metal object found in the ground that can act as a datum?
A steel pin embedded in a footpath (metal disc).
