Current water distribution systems like branch type and separate type piping systems have still had some limitation with instability for temperature and flow rate when using multiple water faucets simultaneously in a house and waste of water resources when using hot water. To improve these problems, we have developed a water-saving type piping system using thermo valve. The present study was undertaken in order to evaluate performance of the improved system compared to the existing system. The results show that our system restrains water waste by 14.9 ℓ maximally in the beginning of using 40℃ water for shower and we can use water at set temperature immediately after residual water circulation of 78~87 seconds. Also, in cases of using multiple water faucets, average temperature deviation was under 0.6℃ and decrement of flow rate reduced over double. Finally, this system contributes to reducing CO2 emission by saving water as well as improving the building environment in terms of water use.