Originally steel workers were planning to do steel work just simply as a net.This type of steel work do not require much time ,care and precision.It also does not have any engineering basis.Probably only due to luck of owner of house,concrete roof thus concreted remain in tact .Considering the fact that most of the houses especially in village areas are being constucted without any professional guidance simply relying on lack of knowlege ,rather than knowledge of the contractor,it is a wonder that buildings remain in tact possibly due to better rains in Kerala.
Even at the time of concrete laying workers prefer the easier way of working rather than following proper and correct engineering standards.
Pictures of concrete laying follows