The design and method of construction has to be no doubt Foolproof .. The type of material used should be of good quality..There should be a foolproof method of supporting the concrete roof constructed and it should be made after proper solidification and fixing of supporting walls.. Further the supporting material can be made of iron well designed in the form of a rod having a flat suppot on top and bottom istaed of bamboos.. Further in case of a multi storied building there should be coir bands supporting the poor labourer from death due to an accidental collapse.. Regards Mahesh Nayathil http://www.maheshnbiomedical.com