Shophouse was introduced to Thailand in Rama 4 reign as a 2 stories building, located next to the developing road. The lower floor was a shop while the upper was a house with a shared party wall between the units. The prevalence of shophouse came from the efficiency of landused and its repetitive design, considered as a high density building before an elevator. The traditional shophouses were an important part in developing city in Thailand as we can see it in our daily life as an everyday heritage.
        Time passed, the city has been developing to become denser. The shophouse is not considered as a high-density building anymore. Furthermore, the problems such as a lack of parking, green space, and an inconvenience compare to the modern buildings cause the truth, which is reflected on census data, that the residents have been moving out. Many are transferred to outsider to do a commercial without living there. Many are still occupied by elder who stick to the places, or cannot find the investors. The situations lead to the inefficient occupying the space as we can frequently find the unused room at the upper floor of each shophouse or sometime a whole unit. It is quite clear that traditional shophouses are obsoleted. Most of it in the inner-city will be continuing demolished in the distant future to develop the denser city. In the time before that, or to keep it longer. it should not exist without its potential utility.
        The “parasite corridor” propose the light structure corridor attach to the shophouse façade. It multiply the possibility of dividing the shophouse unit, to provide the flexibility to manage the leftover space for renting out in any shape and any size as it can to match the demand. Instead of invests the huge money for the whole unit and abandon some space. The project aims to be initial idea on occupying the space in the city more efficiently by exploit the existing unused area to the utmost with least additional structure.

        we aim that the leftovers with minimum extension could be rent out in affordable price per square meter as an alternative choice for the younger working class.