EU 2 Module

2 Plumbing
Systems Part
3
ENGR. FLORIMOND M. ESTEBAN
UC-CEA
S E P T. 2 0 2 2
EU 2 Plumbing Systems – Topic Learning
Objectives
3. Interpret plumbing supply and DWV system design and detailing
information.
DRAINAGE, WASTE AND VENT (DWV) PIPING
SYSTEM
The drainage system is composed of groups of pipes and fittings that convey waste
from the building to the proper means of disposal system.
1. Building Sewer- That part of the horizontal piping of a drainage system which
system which extends from the end of the building and which receives the
discharge of the building drain and conveys it to the public sewer, private sewer,
individual sewage disposal system or other point of disposal.
2. Building drain- the part of the lowest horizontal piping of a plumbing system
which receives the discharge from soil, waste and other drainage pipes inside of a
building and conveys it to the house sewer.
3. Sewage Disposal System. A system for the treatment and disposal of domestic
sewage by means of a septic tank, cesspool, or mechanical treatment, all designed
to serve a single establishment, development or building.
The Drainage System
The drainage system is composed of the piping network within a structure which
conveys sewage, rainwater, or other wastes from their point of origin to a point of
disposal, such as a public sewer or a private treatment facility (septic tank). This system
is often known as the DWV System (Drainage, Waste and Vent).
The Drainage System
The complete drainage system is subdivided into four (4) sub-systems, as follows.
1. SOIL DRAINAGE SYSTEM- The piping that conveys the discharge of water closets or
fixtures having similar functions (containing fecal matter), with or without the
discharges from other fixtures.
2. WASTE DRAINAGE SYTEM or SANITARY DRAINAGE SYSTEM- The piping that receives
the liquid discharge, from plumbing fixtures other than those fixtures (water closets)
receiving fecal matter. This piping is free of fecal flow.
3. STORM DRAINAGE SYSTEM- The piping system that receives clear water drainage
from leaders, downspouts, surface run-off, ground water, subsurface water,
condensate water, cooling water or other similar discharges and conveys them to the
point of disposal. All sanitary wastes must be excluded.
4. VENT SYSTEM- the piping system that receives a flow or air to or from a drainage
system or to provide a circulation of air within such system to protect trap seals from
siphonage or back pressure.
General Requirements
a. The piping must be air tight, gas tight and water tight.
b. Each plumbing fixture, except those with integral traps, shall be
separately
trapped by an approved type water seal trap. This is to prevent odor-
laden and germ-laden to rise out of the drainage system and
contaminate the surrounding air in the room.
c. Each plumbing fixture trap shall be provided with vent pipes. This is
to protect the drainage system against siphonage and back pressure
and to assure air circulation throughout the drainage system.
General Requirements
d. A cleanout, easily accessible, shall be provided for inspection or
cleaning of the pipe run. The location of the cleanout shall be:
- At the upper end of every horizontal waste or soil pipe.
- At every change of horizontal direction of not more than 22.5 degrees
- Within 1.5 m (5’) inside the property line before the house sewer connection
- At every 15m (50’) to a horizontal run of a soil or waste pipe
e. All horizontal piping shall be run in practical alignment and at a
uniform grade of not less than 2% or 2 cm per meter toward the point
of disposal.
General Requirements
f. All horizontal piping shall be supported and anchored at intervals not
to exceed 3 meters.
g. Vertical piping shall be secured at sufficiently close intervals to keep
the pipe in alignment. Stacks shall be properly supported at their bases.
EXCRETA DRAINAGE PIPING
1. Cast iron
2. Ductile iron
3. Galvanized steel (shall not be used underground. Kept at least 152mm above
ground)
4. Galvanized wrought iron (shall not be used underground. Kept at least 152mm
above ground)
5. Lead
6. Copper
7. Brass
8. Series 1000, pvc, dmv
9. Extra strength vitrified clay pipe (shall not be used above ground. At least
300mm below finish ground level.)
10.Approved material having smooth and uniform bore
NOTE: ABS and PVC DWV can be used in high rise buildings at the discretion of the
RMP and with the full consent of the owner.
DRAINAGE FITTINGs

1. Cast Iron
2. Malleable
3. Lead
4. Brass
5. Copper
6. ABS
7. PVC
8. Vitrified clay
VENT PIPES
1. Cast iron
2. Ductile cast iron
3. Galvanized steel
4. Galvanized wrought iron
5. Lead
6. Copper
7. Brass
8. Schedule 40, ABS, DWV
9. Series 1000, PVC, DWV
VENT STACKS

VENT STACKS
1. Copper
2. Cast iron
3. Galvanized wrought iron
4. PVC
VENT FITTINGS

1. Cast Iron
2. Galvanized malleable iron
3. Galvanized steel
4. Lead
5. Copper
6. Brass
7. ABS
8. PVC
Down Spouts
DOWN SPOUT (INTERIOR)
1. Cast iron
2. Galvanized steel
3. Iron
4. Brass
5. Copper
6. Lead
7. Sched 40, ABS, DMV
8. Series 1000, PVC, DWV
DOWNSPOUT (MEDIUM HEIGHT BUILDING)
1. G.I. pipe, sch. 30
2. CISP, S.W.
3. Copper tube, type DWV
4. Sch. 40, ABS, DWV
5. Series 1000, PVC, DWV
Down Spouts
DOWN SPOUT (EXTERIOR/ LOW HT. BLDG)
1. 26 GA, Galvanized sheet metal with steel pipe or cast iron at its lowest section
draining to the catch basin.
DOWN SPOUT (HIGH RISE)
1. Shall be of stronger pipe materials to resist the high hydrostatic pressure.
ROOF DRAIN
1. Cast iron
2. Copper
3. Other corrosion resistant materials
TRAPS (SEC. 1003 NPC 1999)

TRAPS (SEC. 1003 NPC 1999)

1. ABS
2. Cast brass
3. Cast iron
4. Lead
5. PVC
TYPES OF TRAP COMMONLY USED IN
RESIDENTIAL FIXTURES
1. P- Trap→ used at lavatories, sinks, floor drain and scuppers.
2. Drum Trap→used at bathtubs and bidets
3. House Trap
4. Other Appliances
a. Back flow valve
b. Flow control valve
c. Grease trap/ grease interceptor
Drum Trap
Drum Trap- A cylindrical trap commonly used on the drain pipe from a bathtub or under the bathroom
floor.
Back Flow Valve
Back Flow Valve- Device that prevents the reversal of flow which might flood and cause damage to
the building.
SIZES AND CAPACITIES OF GREASE
TRAPS (Page 50 of 57)
Grease Trap

.A device for removing fat and

grease from wastewater by
allowing the retained liquid to cool
and the grease to solidify; then
the grease is separated by
floatation; it rises to the top of the
trap, where it is held. The prime
purpose of a grease trap is to
assure a free-flowing drainage
through pipelines at all times by
intercepting, accumulating and
recovering globules of grease fat
and oils from wastewater.
GREASE TRAP/ GREASE INTERCEPTOR

NOTE:
Grease trap is not required for individual dwelling units or for any private living quarters.
(sec. 1011.1, NPC 1999)
: No food waste disposal unit shall be connected to or discharged into any grease trap. (Sec 1013,
NPC 1999
SIZING OF GRESE INTERCEPTORS
(TABLE 10-4, NPC 1999)
SIZING OF GRESE INTERCEPTORS (TABLE 10-4, NPC 1999)
C= M x W x R x F
WHERE:
C= size of grease interceptors (liquid capacity)
M= Number of meals served at peak hour
R= Waste flow rate;
• With dishwashing machine 6 gallon flow (per meal/ day)
• Without dishwashing machine 5 gallon flow (per meal/ day)
• Single service kitchen 2 gallon flow (per meal/ day)
• Food waste disposer 1 gallon flow (per meal/ day)
• Hospital kitchen 25 gallon / bed / day
F= Storage Factors
• Fully equipped commercial kitchen
8 hour operation: 1
18 hour operation: 2
24 hour operation: 3
• Single service kitchen: 1.5
SAMPLE PROBLEM

Determine the capacity and volume of the grease trap for a canteen that serves
an average of 50 meals a day that is open from 11:00 am to 7:00pm.
SOLUTION: S= M x W x R x F = 50 x 5 x 2.5 x 1
S= → = 625 gallons
M= 50 meals
W=5 cal/ meal/ day
R= 2.5 hours
F= 1
Solve for volume of grease trap (V) m3 (cubic meter)
V= 625/ 264 = 2.37 cubic meter  volume of grease trap
OTHER METHODS USED FOR SIZING THE
GREASE INTERCEPTOR
For grease traps the serve non-scheduled meals to a nonspecific number of
occupants, as in restaurants, fast foods services and luncheonettes;
C = 0.09 (K x N x H x G x S)
Where:
C= Liquid capacity
K= Facility access coefficient
= 1.25 for freeways
= 1.00 for recreation areas
= 0.80 for main highways
= 0.5 for lesser roads
OTHER METHODS USED FOR SIZING THE
GREASE INTERCEPTOR
N= number of seats (use fractional value if occupancy is rarely full)
H= Number of hours per day of operation
G= Waste flow rate (general value is 4.5 Gals)
S= Sewage capacity factor
= 1.7 for outflow to public sewer
= 2.5 for outflow to opposite disposal
• For grease traps that serve scheduled meals to a specific number of occupants as in hospitals ,
nursing homes and schools;
C= 0.14 (M x G x S)
Where;
M= number of scheduled meals served per day; 1, 2 or 3
TYPES OF VENTS
1. Main soil and waste vent
2. Main vent
3. Individual vent or back vent
4. Unit vent
5. Circuit vent or loop vent
6. Relief vent
7. Yoke vent
8. Wet vent
9. Looped vent
10. Utility vent
Main soil and waste vent. The portion of
soil stack pipe above the highest installed
fixture branch extending through the roof.
Individual vent or back vent. The portion of the vent pipe system which serves a single fixture.
Main vent. The principal portion of the
vent pipe system to which vent branches
may be connected. It serves as a
collecting vent line.
Unit vent. The portion of the vent pipe system which ventilates two fixture of similar design
installed on opposite sides of a partition.
Circuit vent or loop vent. The portion of the drainage system which ventilates two or
more fixture traps that discharge into a soil or waste branch.
Relief Vent. The portion of the vent pipe installation that permits additional circulation of air
around the drainage pipes to eliminate back pressure and retardation of waste flow.
Tips for Drainage
Systems
• What is the value of 1
Fixture Unit (D.F.U.)
• Why
• What
Call to Action
• What are 13 minimum standard quantities of fixtures into a of
Plumbing installation as per NPC 1999?
• The minimum size of vent for water closets?
Problem Solving Calculating Net pressure and
Water Demand
3
1 fixture unit (FU) = 1 𝑓𝑡 ൗ𝑚𝑖𝑛
𝑔𝑎𝑙 𝑔𝑎𝑙
= 7.5 ൗ𝑚𝑖𝑛 ~ 8 ൗ𝑚𝑖𝑛
𝐾𝑁 𝑘𝑁
Unit Weight of Water ; 𝛾𝑤 = 7.9 ; 𝑘𝑃𝑎 = 𝑚2
𝑚3
City Main Water Pressure (Baguio City) = 30-60 psi (say 45 psi) = 310𝑘𝑃𝑎
Problem Solving using Charts
To Determine the pipe size with the aid of Table 6.6
1. Choose the Table based on the pressure ranger where the net
pressure at the water meter will fall
2. Select the length column which is equal to or greater than the
required length
3. Follow down the column to a fixture unit value equal or greater than
the total number of fixture units required by the installation
Problem Solving using Charts
Example 1
Determine the size of the pipe that is connected to 2 Water closets, 2
lavatories, 1 kitchen sink and 1 Bathtub. The length of the pipe is 5
meters. City Main Water Pressure = 30-60 psi (say 45 psi) = 310 kPa
Compute for the water demand and Determine the pipe size
Computing for the water demand and
Determining the pipe size
Compute for the water demand and Determine the pipe size
Assumptions:
3
1 fixture unit (FU) = 1 𝑓𝑡 ൗ𝑚𝑖𝑛
𝑔𝑎𝑙 𝑔𝑎𝑙
= 7.5 ൗ𝑚𝑖𝑛 ~ 8 ൗ𝑚𝑖𝑛
𝐾𝑁 𝑘𝑁
𝛾𝑤 = 7.9 𝑚3
; 𝑘𝑃𝑎 = 𝑚2
City Main Water Pressure = 30-60 psi (say 45 psi) = = 310𝑘𝑃𝑎

From Table 6.5

qty Fixture Water Fixture Unit (WFU) Total WFU
1 Water Closet 3 3 X1 = 3 WSFU
1 Lavatory 1 1 X1 = 1 WSFU
1 Kitchen Sink 2 2 X 1= 2 WSFU
TOTAL = 6 WSFU
Computing for the water demand and
Determining the pipe size
Compute for the water demand and Determine the pipe size
Total water demand = 6 WSFU
1. Total water demand = 6 WSFU x 8 𝑔𝑎𝑙 ⁄ min = 48 𝑔𝑎𝑙 ⁄ min
A. Determine the pipe size with the aid of Table 6.6
B. Choose the Table based on the pressure ranger where the net pressure at the water meter
will fall.
C. Select the length column which is equal to or greater than the required length
D. Follow down the column to a fixture unit value equal or greater than the total number of
fixture units required by the installation
Say From Table using P= 310 kPa
Service Pipe = 19 mm Pipe ∅ or 3⁄4 " ∅ pipe
Branches = 13 mm Pipe ∅ or 1⁄2 " ∅ pipe
Problem Solving using Charts
Example 2
Given the Plumbing Layout
One Storey Residential Building
Computed Length of remote fixture = 9 meters
1 Water Closet
1 Lavatory
1 Kitchen Sink
City Main Water Pressure = 30-60 psi (say 45 psi) = 310 kPa
Compute for the water demand and Determine the pipe size
Problem Solving using Charts
To Determine the pipe size with the aid of Table 6.6
1. Choose the Table based on the pressure ranger where the net
pressure at the water meter will fall
2. Select the length column which is equal to or greater than the
required length
3. Follow down the column to a fixture unit value equal or greater than
the total number of fixture units required by the installation
Example 2
Determine the size of the pipe that is connected to 2 Water closets, 2
lavatories, I kitchen sink and 1 Bathtub. The length of the pipe is 5
meters. For the City Main , use 𝑃𝑎𝑣𝑒 = 310𝑘𝑃𝑎

Water Fixture Unit

QTY Fixture Total WSFU
(WSFU)

2 Water Closet 3 2 X 3 = 6 WSFU

2 Lavatory 1 2 X 1 = 2 WSFU
1 Kitchen Sink 2 2 X 1 = 2 WSFU
1 Bathtub 2 1 X 2 = 2 WSFU
TOTAL = 12 WSFU
Example 2
Determine the size of the pipe that is connected to 2 Water closets, 2
lavatories, I kitchen sink and 1 Bathtub. The length of the pipe is 5
meters. For the City Main , use 𝑃𝑎𝑣𝑒 = 310𝑘𝑃𝑎
𝑔𝑎𝑙 𝑔𝑎𝑙
Water Demand = 12 WSFU x 8 ൗ𝑚𝑖𝑛 = 96 ൗ𝑚𝑖𝑛
𝑃𝑠𝑡𝑎𝑡𝑖𝑐 = 0
𝑃 = 𝑃𝑎𝑣𝑒 − 𝑃𝑠𝑡𝑎𝑡𝑖𝑐
𝑃 = 310 − 0 therefore 𝑃 = 310 𝑘𝑃𝑎
Say From Table using 𝑃 = 310 𝑘𝑃𝑎
Service Pipe = 19 𝑚𝑚 𝑃𝑖𝑝𝑒 ∅ or 3⁄4 " ∅ 𝑝𝑖𝑝𝑒
Branches = 19 𝑚𝑚 𝑃𝑖𝑝𝑒 ∅ or 3⁄4 " ∅ 𝑝𝑖𝑝𝑒
Problem Solving using Charts
Example 3
Given a commercial 2 Story commercial building with the following:
Determine the size of the pipe that is connected to 5 Water closets, 5
lavatories, 2 kitchen sinks and 3 Bathtubs. The computed length of the
pipe is 27 meters. The Story height is 3 meters. The Pressure main is
320 𝑘𝑃𝑎
Problem Solving using Charts
Example 3

Water Fixture
QTY Fixture Total WSFU
Unit (WSFU)

5 Water Closet 5 5 x 5 = 25WSFU

5 Lavatory 2 5 X 2 = 10 WSFU

2 Kitchen Sink 4 2 X 4 = 8 WSFU

3 Bathtub 4 3 X 4 = 12WSFU
10 Urinal 3 10 x 3= 30 WSFU

TOTAL = 85 WSFU
Example 2
Example 3
Given a commercial 2 Story commercial building with the following:
Determine the size of the pipe that is connected to 5 Water closets, 5 lavatories, 2 kitchen
sinks and 3 Bathtubs. The computed length of the pipe is 27 meters. The Story height is 3
meters. The Pressure main is 320 𝑘𝑃𝑎. Calculate for the water demand, Service and branch
pipe sizes.
Water Demand = 85 WSFU x 8 𝑔𝑎𝑙ൗ𝑚𝑖𝑛 = 680 𝑔𝑎𝑙ൗ𝑚𝑖𝑛
Calculate for the net pressure
𝐾𝑁
𝑃𝑠𝑡𝑎𝑡𝑖𝑐 = 9.79 3 ∗ (3m) = 29.37𝑘𝑃𝑎
𝑚
𝑃 = 𝑃𝑎𝑣𝑒 − 𝑃𝑠𝑡𝑎𝑡𝑖𝑐
𝑃 = 320 − 29.37 = 290.63 𝑘𝑃𝑎
Say From Table using 𝑃 = 290.63 𝑘𝑃𝑎
Service Pipe = 38 𝑚𝑚 𝑃𝑖𝑝𝑒 ∅ or 1 1⁄2 " ∅ 𝑝𝑖𝑝𝑒
Branches = 38 𝑚𝑚 𝑃𝑖𝑝𝑒 ∅ or 1 1⁄2 " ∅ 𝑝𝑖𝑝𝑒
DRAINAGE, WASTE AND VENT (DWV) PIPING
SYSTEM
The drainage system is composed of groups of pipes and fittings that convey waste
from the building to the proper means of disposal system.
1. Building Sewer- That part of the horizontal piping of a drainage system which
system which extends from the end of the building and which receives the
discharge of the building drain and conveys it to the public sewer, private sewer,
individual sewage disposal system or other point of disposal.
2. Building drain- the part of the lowest horizontal piping of a plumbing system
which receives the discharge from soil, waste and other drainage pipes inside of a
building and conveys it to the house sewer.
3. Sewage Disposal System. A system for the treatment and disposal of domestic
sewage by means of a septic tank, cesspool, or mechanical treatment, all designed
to serve a single establishment, development or building.
The drainage piping system contains fittings that serve as drains, traps and vents.
Drainage Piping System
The drainage piping system contains fittings that serve as drains, traps and vents.
Drains- fittings used for draining fluid from point of use to the piping system.

Traps- fittings or device designed and constructed to provide a liquid seal which prevent
the back passage of air without materially affecting the flow of sewage or water through it.

Vents-pipes and fittings installed in the system to provide air circulation so as to protect
trap seals from siphonage and back pressure.
Thank You!

Email
fmesteban@uc-bcf.edu.ph