Why Prefab house?

A prefabricated structure, is a structure which has components manufactured in an off-site industrial facility. They are sometimes referred to as factory-made or modular structures, although there are some notable differences. In a prefab structure, components are made in house and transported in a flat-pack form lowering logistical costs, whereas modular homes have entire sections of the given structure built off site. By opting for Prefab; human error, waste, time, energy & costs are significantly reduced allowing for efficient construction.
After Great earth quake in Nepal in 2015 most of the constructions ,like, home ,shelter,factort,&many outlets are are constructed by prefab system