This paper aims to identify the difference of housing development location and type, and middle-class residents' preference of housing choice between before and after the urban rail transit in Bangkok Metropolitan Region (BMR) and examine whether the urban rail transit prevents urban sprawling and its extent of the effect.
From the comparison of housing development location and type (low-rise housing development and condominium/apartment) from the digital map in 2006 and 2013, it is found that housing development concentrated only in Bangkok city and Nonthaburi province before 2006 and it widespread to Northern and Southern provinces after 2006. However, in Bangkok City, housing development shifted inward after 2006. Before 2006, the major housing type is the low-rise housing development, which is consist of detached houses and townhouses but after 2006, the condominium/apartment became the majority.
A questionnaire survey was conducted to middle-class residents with school-year children in BMR, and the result was analyzed by the conjoint method to reveal their housing preference. From the conjoint analysis, it is found that they consider the housing type (detached house) is the most important and next is the access to the train station. Conjoint analysis by each generation shows that respondents in 40s and 50s have the same tendency but 50s' attachment to the housing type (detached house) is much stronger than 40s. On the other hand, respondents in 20s and 30s have the different tendency, and they consider the access to the train station is the most important and the next is access to the main road.
It is impossible to reveal the causal relationship between the development of urban rail transit and change in housing development, and housing preference. However, it can be inferred that development of urban rail transit leaded condominium development near their stations and its changed young generation's housing preference and this change lead housing location inward in Bangkok city. Thus, the result of this research implies that development of urban rail transit prevents housing sprawling in Bangkok City but its effect area is limited to the neighboring area, therefore now housing developing is still spreading outward in BMR. To prevent housing sprawling, the extension or new development of urban rail transit in the suburbs is essential. Also supplying larger units in condominiums near the railway stations in suburbs will attract household with children to live near and is expected to prevent sprawling.