Jí Architect entrusted by client, redeveloped an approx. 90-square meter atypical courtyard house in a Beijing hutong. Functions of the redeveloped courtyard house were yet to be decided. The outline and the shape of the new building shall remain consistent with the original.The original building constructed in the 1980s was a dilapidated hutong house with flat roof. The ground level of the courtyard in-between was lower than the repaired alleyways outside the yard. The clear ceiling height of the both two floors in the northern part building was less than two meters. Peoples had to lower their heads to avoid bumping the wooden beams when walking through the room.Due to the variety of requirements and limitations of the redevelopment and construction in hutong area, the design becomes a process of finding the optimal solution by using the limits.