MEGA House, Taipei, Taiwan: Duct work is connected to the earth tube located outside in the ground and brings fresh air into the house after it gets filtered through the nano-air filter. (Photo by Mignon O’Young) MEGA House, Taipei, Taiwan: Duct work is connected to the earth tube located outside in the ground and brings fresh air into the house after it gets filtered through the nano-air filter. (Photo by Mignon O’Young)