Foundation transmits load of super structure to soil. Generally it is below the ground level. If some part of foundation is above ground level, it is also covered with earth filling. This portion of structure is not in contact of air, light etc, or to say that it is the hidden part of the structure.
The depth and width of foundation should be according to structural design.
-The depth of the foundation should not be less than 1 meter in case the design is not available.
-The length, width and depth of excavation should be checked with the help of center line and level marked on the burjis.
-The excavated material/ earth should be dumped at a distance of 1 meter from the edges. Work should be done on dry soil.
-Arrangement of water pump should be made for pumping out rain water.
-The bottom layer of the foundation should be compacted.
-There should be no soft places in foundation due to roots etc.
-Any soft/ defective spots should be dug out and be filled with concrete/ hard material