The government has implemented various policies to promote long-life housing including the mandate of certification system and incentives for achieving excellent grades. Despite the recent research of a pilot project to review the possibilities of reducing cost increases in higher grades, the comparatively high initial construction cost is still one of the main obstacles to adopting long-life housing. This study discussed the economic effects of long-life housing in a longterm perspective as an effort to find the logical grounds to encourage it. The five scenarios during 100 years were developed for long-life housing by grades and non long-life housing with the cycle time of 40 years. Then, life cycle costs (LCC) of those scenarios were calculated in the format of unit cost including design fees, construction costs, overhead, maintenance costs, repair costs, demolition costs, etc. As a result, up to 10~20% of LCC could be reduced by employing long-life housing. The sensitivity analyses were also conducted to check the variations of effects by changes of the discount rates and cycle times. In conclusion, it is worthwhile to spread long-life housing to decrease the public waste in socio-economic aspect. Additional studies should be followed for more realistic estimation of LCC by supplementing scenarios and base cost data.