Public Measures and Support
The biggest task to be tackled should be the reinforcement of existing wooden houses with insufficient quake-resistance as well as that of newly built buildings. By simply nailing a sheet of plywood to a corner of the exterior wall, the earthquake resistance could be vastly improved. Condominiums with low earthquake-resistance also should be reinforced as soon as possible.
The national government established the Law to Facilitate Seismic Retrofit for Buildings. It is, however, insufficient, with what was experienced in the Great Hanshin Earthquake not being reflected and cannot guarantee the people's safety. Meanwhile, some municipalities have worked out some support measurements.
The Case of Yokohama City
Yokohama city is a municipality which has been supporting the earthquake-resistance improvement more than any others. It launched a free seismic-capacity evaluation service in 1995, a subsidy system for quake-resistance improvement of wooden houses for up to one-third or two million yen in 1999. Over 7,800 houses had the diagnosis by the end of November, 2001, and about one-third of those were diagnosed to be "in danger" and 85 actually received improvement works.
Another important housing-related issue should be the seismic retrofit of condominiums with piloti. It is quite inexpensive to strengthen the building with diagonal bracings and steel piping -- several hundred thousand yen per house.
There are about 13 million houses which do not meet the present standard in Japan. 13 trillion yen will be required if subsidy of one million yen is given out per house for the reinforcement work. It will be 2.5 trillion yen a year if it is to be carried out as a five-year plan, which is quite feasible.