BRE349 Plumbing

Plumbing System Design
Case Study on
Workingview Commercial Building

Content
1. Background Information
2. Plumbing System Arrangement
3. Water Demand
4. Water Storage
5. Pipe Sizing
6. Pipe Materials
7. Other Consideration

Background Information
Name: Workingview Commercial Building
Address: 21 Yiu Wah Street, Causeway Bay, Hong Kong
Year of completion: 1994
Main usage: Commercial offices
No. of storey: 26

Plumbing System Arrangement
1. Indirect Water Supply System: Fresh & Flush
Water
2. Sump and Pump System
3. Gravity Supply System
4. Pressure Reducing Valve (PRV)

Water Demand
● Consumption of water in the building depends on building type, appliance capacity, etc.
● provide an optimal water flow rate and water pressure ensure the delivery of water to all flats
● consider the maximum frequency of use average water usage rate and time reliability and risk management

Water Demand
●
●
●
●
●

Government supply main
Position of check meter
Copper pipe for potable water
PVC pipe for flushing water transfer to pump room and then roof

Water Demand building type: commercial building number of occupants: 6 flats each floor and 26 storeys
1 wash basin and 1 wc cistern at each flat

Water Demand
•Most fittings are used only at irregular intervals
• It is unlikely that all the appliances will be used simultaneously • No need to size pipework on continuous maximum

Water Demand
Apply probability theory,
• Assume random usage with fittings
• Determine maximum frequencies of use
• Estimate average water usage rates & time

Water Demand
Loading unit
A factor given to an appliance relating the flow rate
To evaluate the probable maximum water usage Relates the flow rate to probable usage

Water storage
• Water tank on top roof
• Provide enough water supply
• Provide pressure

• Same design of flush water and fresh water but separate

• Distribute water to different room by gravity

• Pressure reducing valve is needed excess 10 storeys

Water storage