12 meters. According to the online housing search, Zhejiang has issued policies that stipulate that new rural housing must not exceed three floors and the height of the building must not exceed 12 meters. Zhejiang has issued regulations that self-built houses by villagers cannot exceed 3 floors and the floor height must not exceed 3.5 meters. Therefore, the maximum height of self-built houses in Tonglu, Zhejiang is 12 meters.