Located near seaside context and rich natural ecologies of the mangrove beach of Bangkok’s outskirt - Bang Khun Thain, Habitia-H Club facilitates a recreational function as a clubhouse and a gateway entrance for a housing estate “Sansiri”. Habitia-H Club is a one- storey building situated in a 1,750-square meter site area with a 302-square meter floor area. The owner’s requirement is to create the architecture demonstrating an impressive impact with the combination function of a leisure center and a main gateway. How to design and combine these two different characteristics of space between private and public, indoor and outdoor; be- comes an interesting condition that need to be solved with a new approach of concept design.