using elevated water tank

Background:

You can still have a water supply when there is a blackout. If you use a booster pump, you just need to create a bypass system.

If there is no existing/ dedicated structure to support the tank, you must make one and it is usually not cheap to construct due to structural integrity consideration.

Occupants of the house are usually 4 people. According to the statistics taken from Pergub DKI Jakarta No: 122/2005 (Regulations of Jakarta's Governor), every occupant of a typical dwelling house in Jakarta approximately consumes 150 liters a day. For 4 people, it would be 600 liters a day. To prepare for the possibility of 2 days blackout, a tank with a capacity of 1200 liters is needed. There are many manufacturers of plastic tanks but Penguin was chosen for this project.
The structure to support the tank must be able to take at least 1,200kg of water plus the empty weight of the tank (38kg). After consulting a friend who is a civil engineer, I planned to install columns in the kitchen area with the below structure.

The tank would sit on a triangular surface initially planned to be l-shaped beams. However, a concrete structure is chosen for a cheaper cost.

A booster pump can help to provide a stronger water pressure. How to choose the pump? The main criteria are the pump should be sufficiently quiet when running, can deliver enough debit of water, and must be automatic. Since it will mostly send the water to taps at a lower height, no particular attention is given about the pump's max head. The pumps in the market normally have sufficient head. For this house, the booster pump highlighted in yellow is chosen

Now it is time to run the pipes. Here is the schematic of the piping created using AutoCAD. UPVC pipes were chosen due to their good UV resistance, cheaper cost, durability, recyclable capability, and ease of installation. It is important to make sure they can survive the typical outdoor condition in your area. As for the size, 1" pipes are preferable because it is the highest possible size that can fit the ports of the booster pump. Why must we choose the biggest possible size? Remember Darcy-Weisbach equation? The bigger the diameter, the smaller the pressure loss (this means you save energy). Since the booster pump is not normally used, we need to conserve the energy of the water flowing in pipelines to get sufficient pressure in taps.

As mentioned above, a bypass system of the pump is used for normal operation. The pictures below show the bypass system. Normally, the booster pump is off. The orange ball valve beside the yellow one should be open for the bypass system to work. House occupant can access all the ball valves easily via the opening shown (the window was not installed at that time).