To set out a building after transferring the architectural proposal from drawing into the ground. It establishes location points of the site boundaries, columns, foundation, centre line of wall and other necessary data and level.
The whole structure will be located due to this initial set out. Accurate set out is the key part of this construction work and errors are very expensive & it needs so much time for correction.
The structure position and orientation is generally detailed in engineers drawing, and it showed how the layout would be arranged.
The controlling points of the structure are marked. After that, all the operations will proceed.
At first, You need to mark the building layout and tied a line to the corner posts, a nail in the top of the post.
A theodolite is placed to find out the corners at 90-degree angle after that ranging rod is required to find the straight line between two points.
Corner posts are usually timber posts which are usually 50 mm x 50 mm set in the ground and marked with a nail at the centre of the centre.
The outlines are marked by dry lime powder.
Profile boards are set at a height of 0.6-1 meter.
When the outline of a building is more complex than a simple rectangle, then it's necessary to fix up some points.
Sometimes for the irregular building shape, at first layout a large rectangle which will cover the entire building. Once it will be done deductions, and alternative can be made to obtain the layout.