Overhead Water Tank
The overhead water tank should be in the southwest (best) or west corners of the building. An overhead water tank should not be located in the northeast or southeast corners, or in the middle of the roof. It is also best that it is not located in the northwest unless the tank is small and is located approximately 1m (2 or 3 ft) from the building’s corner. The tank should be elevated at least 1m (2 or 3 ft) above the roof, on a platform.
If possible, the tank should not be made of plastic. If it must be plastic, however, it should either be black or dark blue plastic, because such colors aid the absorption of sunlight. A dark water tank while absorbing sun for heat doesn’t encourage microbial growth as quickly as a light-colored tank would do.
If possible, there should be different tanks for the kitchen and bathrooms.