Both Hot and Cold water must be supplied throughout the restaurant to different appliances and fixtures. This includes two bathrooms, two kitchen sinks, two dishwashers, a washing machine, an icemaker, and coffeemaker. The following shows the flow rates for the different fixtures in wsfu, GPM and CFM:
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From the chart it was determined that the maximum flow required would be 8 GPM at the sinks. Using this chart and with the water at a pressure of 60 psi, it was determined that 1/2″ copper pipe could be used throughout the building. Using an estimate of 35 gallons per day per occupant, and an occupancy of 170, the restaurant uses about 6,000 gallons of water per day. This breaks down to approximately 2,700 gallons of cold water and 3,300 gallons of hot water per day.
Hot & Cold Water Distribution Single Line Diagram
As indicated in the legend next to the drawing, Cyan pipe indicates city cold water supply delivered into the building from the west. This supply then is split into two lines of 1/2″ copper pipes for the building water distribution. Blue line indicates cold water and magenta indicates hot water. Hot water line first goes through the gas powered 40 gal water heater, and then is routed to the appropriate appliances.
The sanitary piping plan is shown below. As indicated in the legend, the green piping demonstrates the building sewer drainage plan (8″ diameter piping), and the red piping demonstrates the city sanitary sewer piping. All of the outlets have sewer piping directed to the city sewer system. All of the sewer piping in under ground and under slab.
Bathrooms and sinks are connected as per below indicated riser diagram. Because the building is a single story structure, no extensive multi-story vertical diagrams are necessary.
Sources:
http://www.about-building-in-canada.com/plumbing.html
International Building Code 2009
International Plumbing Code 2009
Electrical and Plumbing Design 