Which water supply system suits a multistory home?

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Which water supply system suits a multistory home?

Water supply systems are divided into 2 main types:
Up-feed systems ( feed up) and down-feed systems ( feed down)
Today we discuss up-feed systems, where the main pipe starts on the lowest floor and supplies that floor first, followed by the second and third floors,

continuing upward so that the top floor receives water last. Our example is a small building with relatively few floors, such as a residential home with 2 to 3 floors

Up-feed water supply can be divided into  

1. Direct supply from the water authority's mains pipe  

Suppose water must be supplied up to 3 floors. For a rough estimate, each floor is approximately 3 meters high, and the mains pipe is buried

beneath the house at a depth of approximately 50 centimeters. If drawings are available, estimate from them. Water must therefore reach the highest outlet on the

third floor   The total elevation is half a meter below ground, plus 2 meters through the first floor, plus 3 meters through the second floor, plus approximately 2 meters to the

outlet on the third floor.   The total is approximately 8.5 meters through which water must be pumped. Meters of water can be converted to the commonly used pressure unit

bar ( bar) by approximating that 10 meters of water equals 1 bar The head required to pump water from the mains to the outlet on the

third floor is therefore 0.85 bar In reality, friction losses ( friction loss) in the pipe must also be calculated, requiring details

of the complete pipe system, including diameters, lengths, fittings, elbows, reducers and branches. For a household water supply,

a simpler approach can be used. Detailed calculations are reserved for applications needing precision, such as industrial

factory or refinery pipe systems. These require thorough calculations, usually with computers and software.
A simple method for estimating friction loss in household water supply piping is to use a percentage allowance.  
This is a general approximation, and the percentage varies between people. I normally use 30% For example, our three-story house

requires an elevation head of 0.85 bar so I allow for friction loss by adding 30% giving 1.3 x 0.85 = 1.105

or approximately 1.1 bar But we must also add an outlet pressure of 1 bar as well,   so that water flows fully at the destination and

has enough pressure for use and connection to sanitary fixtures. The total head needed to reach the highest outlet, including

pipe losses and outlet pressure, is therefore 2.1 bar as calculated.

Normally,   mains water pressure has a standard minimum of 2 bar  This means that for an ordinary three-story house,
water can be connected from the mains passing the house, with sufficient pressure for all three floors. Sometimes, however, the supply is interrupted or pressure drops, so we need to install water pump to maintain consistent performance.

2. Supply through water pump for the house itself
Water delivery is similar to the first arrangement, but additional equipment is needed between the mains and the house. We require
- a storage tank containing an on/off valve called “ a float valve ( float valve)” When the water level falls, the valve opens; when the tank is full, it closes. Overflow indicates that the valve has failed.
- water pump to water pump from the storage tank for household use.

People generally do not use water continuously. A tap may be opened briefly for handwashing, or a toilet flushed once, or

several times.   To prevent frequent pump starts and stops, which shorten pump life and waste electricity, a pressure tank

(accumulate tank) must be added. Operation is simple: the pump fills the pressure tank and stops when the set pressure is reached.

When water is used, such as for handwashing or toilet flushing, it comes from the pressure tank first. Repeated use or a tap left open

for a long time lowers tank pressure. At the preset value, the pump starts to refill the pressure tank. The tank therefore

allows the pump to operate in longer continuous runs and rest for longer periods.