Every building has its own features, it is very necessary to prepare a Layout Plan and Foundation Plan first. By following the grids on the layout/ foundation plan mark them on the ground. With the reference of the grids, mark the width of foundations also. It is similar to drawing the building on the drawing paper, but the difference is; it is drawn on the ground with full size scale. Remember that the width of foundations are designed by the Structural Engineer according to the Safe Bearing Capacity of the soil.
There are some precautions in setting out, the most important is the squraeness of rooms and precise measurement, second is the measurement should be taken perfectly horizontal and keeping the measuring tape tight.
After completing the setting out of building, get it checked by some experienced Architect, Site Engineer or Construction Manager.
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