Managing life cycle cost of public facilities is a hot issue, since central and local governments are facing severe fiscal conditions. This paper expands facility location model to include increasing maintenance cost, efficient utilization of existing facilities, and conversion to the appropriate use of public facilities due to demand change by aging society. The model is then applied to facility location in one-dimensional city that has two types of population, schoolchild and elderly, and facilities for each population. Applying the model to three scenarios of population distribution change, we found out that utilizing existing facilities and conversion allow us to make more facilities and lower travel cost, and that the compactation scenario and centralized population scenario are suitable for applying conversion due to low travel cost and great effect of conversion on reducing travel.