Most Sudanese live in simple houses of their own or rent from landlords or agricultural-scheme authorities. At last report, over half of all housing units were gottias—single rooms with round mud walls and a conical straw roof; about one-third were menzils—multi-room houses with toilet facilities. Of all dwellings, over 80% were owned. Almost every house, even in the cities, has a walled courtyard or garden. In the big cities, bungalows are provided for important government officials and high-level foreign employees. A national housing authority provides low-cost housing to government employees, rural schoolteachers, and persons in low-income groups. A town-planning ordinance provides for slum clearance and replanning of towns. Khartoum has a number of modern apartment buildings.