Water Sizing

1
Water Sizing

• Plumbing Systems
• CNST 305
• Environmental Systems 1
• Dr. Berryman

2
Steps to sizing

3
Isometric Diagram
30o
4
Assign WSFU
2 WSFU x .75 1.5
5 WSFU
10 WSFU
1 ¼ spud

• Water Supply Fixture Unit (WSFU)
• Use Table 2-2 (Wentz) for WSFU assignmentpp 7-12
• See note 3 (fine print on bottom)

5
Add Up All WSFU
110 WSFU
21 WSFU
3 WSFU
1.5 WSFU
1.5 WSFU
8 WSFU
3 WSFU
1.5 WSFU
1.5 WSFU
13 WSFU
5 WSFU
23 WSFU
5 WSFU
33 WSFU
10 WSFU
143 WSFU
24 WSFU
10 WSFU
6
Convert to GPM
7
Select Chart and Size
1 ¼ spud

• Note
• Use copper pipe
• Use minimum size from tbl 2.2 for individual
  fixture pipe

8
Predominantly Flushometers for Smooth Copper Pipe
2 ½
2
2
1½
1½
1
¾

• Notes
• 5-10 fps
• 2-7 psi/100

9
Class Exercise

• You size the hot water piping
• Does the hot water side use flushometers?
• Use predominately flush tanks

10
Check

• 5-10 fps
• 2-7 psi/100
• Pressure at last fixture

11
Notable notes

• Booster pumps
• Need for boost water pressure to overcome static
  head and friction
• Sizing
• (A) Available water pressure
• (B) Pressure required at last fixture
• (C) Static head losses
• (D) Friction losses
• Equivalent length
• Pressure drop through backflow preventors, meter,
  water softeners, and filters
• A (BCD) required boost

12
Next Time

• Assignment 1
• Due Monday beginning of class
• Problem 9 in Chapter 8 of Wentz, pp. 132
• Drain Waste Vents (DWV)