This house for parents located on Amami-Oshima Island where is severe subtropical climate and often hit by typhoon. To accommodate this condition, a rectangular roof which is supported by 4 meter-span steel framework structure was installed. This roof create environment as if it is comfortable habitat under trees. Concrete walls stand independent from roof structure to achieve floor plan without any restriction by steel columns for the roof. The continuously projecting concrete wall create impression that Living Room is expanding toward the rich external landscape of this island.