Dwelling types can be divided into three broad categories: formal, informal and 'traditional'. Children who live in formal housing are more likely to have access to basic services and other social infrastructure provided to formal residential areas.
Children are defined as living in overcrowded dwellings when there is a ratio of more than two people per room (excluding bathrooms but including kitchen and living room). Thus, a dwelling with two bedrooms, a kitchen and sitting-room would be counted as overcrowded if there were more than eight household members.
Adequate sanitation includes flush toilets and ventilated pit latrines that dispose of waste safely and are within or near a house. Inadequate sanitation includes pit latrines that are not ventilated, chemical toilets, bucket toilets, or no toilets at all.
Access to electricity in the physical structure of a house is important for a range of reasons. Where there is no electricity, families use other fuels for lighting, heating and cooking, and these can pose health hazards.