International Journal of Engineering and Technology

In the North Sulawesi Province in Indonesia, more than 90% of buildings use corrugated galvanized zinc roofing. A zinc roof may cause overheating in the room if no proper treatment is implemented according to the thermal properties of the material. This study aims to find out the cooling of galvanized zinc-roofs by using an automatic water spraying to lower indoor air temperatures in buildings in humid tropical climates. Spraying water onto the roof surface is performed on the test cell and it can reduce the average roof surface temperature by up to 5 °C, but water should be sprayed about 10–15 minutes continuously. Automatic water spraying can control indoor temperatures below the exterior temperature, but still cannot reach the comfort temperature especially during the day. By spraying it is advantageous to lower the temperature to about 1.55 °C less than the comfort temperature than without spraying. Further research is needed, primarily to conserve the used water by reusing it and also cooling it again.