Overharvesting of forest materials to construct bush houses leads to erosion and unproductive soil. Habitat houses are designed to withstand the elements Well-constructed Habitat houses protect families from rain and cyclones, as well as saving on labor and forest land. Habitat’s work in Papua New Guinea Habitat Papua New Guinea has built more than 1,000 Habitat houses. Average house cost: US$8,590.* *House costs fluctuate.