Based on the 500-meter mesh data of the 2005 National Census and using geographic information system (GIS), Attractors Lab estimated the number of general households located within a 1 km radius of the coastline of the three prefectures. The company considers the figure may be used to estimate the number of temporary housing units needed in the days to come.

Of the 150,000 households, 11% (17,000 households) have children under the age of 6 who have not started school. The number of households with elderly family members over the age of 65 is 77,000, accounting for 50% of the total.

As the number of single-person households of elderly over 65 vastly outnumbers the number of single-person households of young people in their 20s, Attractors Lab suggested that Japanese-style housing will be the preferred style for temporary housing units.

Residential floor areas in these localities are quite large and the company estimates the average floor area to be around 110 m2. While households with four people account for 15% and those with five or more people account for 17%, some households may have to be divided if temporary housing is urban-style small units.

The company points out that it may be necessary to allocate two units for large families.

According to the police authority, number of houses confirmed lost or severely damaged in the disaster exceeds 23,000 as of March 23.