There are lot of wrong concepts,beliefs and wrong practices on construction of houses in Kerala depending upon location.As I have built houses in almost all parts of Kerala,I have come across these local practices and beliefs many a time and had tough time convincing local people especially in the interior parts of Kerala as almost the entire population around construction site will come to the site to supervise,question and offer free advices and suggestions sometimes cautioning the owner,sometimes threatening him with dire consequences and always opposing what we “coming from Cochin” are doing.
First of all you have to assess the soil condition technically.In stable soil conditions,an experienced Construction Engineer will be able to assess the soil nature and suggest appropriate foundation design.In places like Cochin where most of the land is filled up or marshy area with practically not even a trace of sand even up to depths as high as 40 feet,a proper professional soil test will be essential to find out what type of foundation will be required.
While conducting such a soil test they will dig the place where the house has to come up up to about 45 feet and will collect samples of soil on the way to depths.These samples of soil will be tested in Engineering laboratory and a proper professional soil test report will be given to you.This report will be passed on to a Structural Consultant(An Engineer who has done post graduation in Structural Engineering) preferably with experience in designing structures for many years in that area.
Structural consultant will give a foundation design prepared using a software called STAAD in consultation with the Construction Engineer/Architect concerned.For smaller plots one bore for soil test will be sufficient normally done at centre of the plot.For bigger plots,more no of soil test bores will have to be used.