2. BUILDING SANITARY DRAINAGE SYSTEMS
TWO-PIPE SYSTEM - INDPENDENT STACKS FOR
SOIL AND WASTE WATER WITH ASP.
ONE-PIPE SYSTEM- COMBINED STACK FOR
SOIL AND WASTE WATER WITH ANTI
SIPHONAGE PIPE.
SINGLE STACK SYSTEM- COMBINED STACK
FOR SOIL AND WASTE WATER WITH OUT ANTI
SIPHONAGE PIPE.
SINGLE STACK(PARTIALLY VENTILATED)
SYSTEM- VIA MEDIA BETWEEN ONE PIPE AND
SINGLE STACK. ONLY SOIL TRAPS ARE
VENTILATED.
6. CHOICE OF PLUMBING SYSTEM
AS PER SP:35 (S&T)-1987
TWO PIPE SYSTEM IS AGE OLD AND SAFE SYSTEM.
ADVANTAGEOUS WHERE WASTE WATER IS RECYCLED FOR USE IN
GARDENING ETC. NOT RELEVANT IN THE CASE OF JAYPEE
GREENS.
REASONING BEHIND THE SEGREGATION OF THE SOIL AND WASTE
STACKS HAS BEEN TO PUT SECOND LINE OF DEFENCE IN THE
FORM OF TRAPPED GULLY AGAINST PASSAGE OF SEWER AIR INTO
THE BUILDING VIA WASTE FIXTURES.
THIS WAS CONSIDERED A SERIOUS DEFECT SINCE THE FOUL AIR
FROM WASTE PIPE INTO A BUILDING MAY BE AS OBJECTIONABLE
AS FOUL AIR FROM SOIL PIPE. IT WAS CONSIDERED THAT THERE IS
NO SECOND LINE OF DEFENCE AND SEPARATE PIPE FOR WASTE
WATER IS NOT REQUIRED.
ONE PIPE SYSTEM IS TO BE PREFERRED WHERE BUILING
PROVIDES FOR SUITABLE GROUPING OF ALL SOIL AND WASTE
APPLIANCES AND WHERE ALL TYPES OF WATERS ARE TAKEN TO A
COMMON SEWER TO THE PLACE OF DISPOSAL OR TREATMENT.
TRAP SEAL OF 40MM AND 50 MM FOR WASTE AND SOIL WATER
RESPECTIVELY CONSIDERED SUFFICIENT SAFEGUARD.
7. CHOICE OF PLUMBING SYSTEM
AS PER SP:35 (S&T)-1987
CONTD….
IN ADDITION FOLLOWING SAFEGUARDS ARE TO BE TAKEN:-
EACH WASTE PIPE CONNECTED ABOVE SOIL BRANCH TO COMMON
STACK.
ALL TRAPS SHALL BE VENTILATED BY LOOP VENTS BY A PIPE NOT
LESS THAN 50MM DIA.
MODERN TREND IS TO GO IN FOR PARTIALLY VENTILATED ONE
PIPE OR SINGLE STACK SYSTEM.
IN HIGH RISE BUILDINGS, PARTIALLY VENTILATED ONE PIPE OR
SINGLE STACK SYSTEM IS BEING USED WHERE VENT STACK IS
CONNECTED TO THE DRAINAGE STACK OR THE SOIL APPLIANCES
AT EACH OR ALTERNATE FLOOR. FOLLOWING SAFEGUARDS TO BE
TAKEN IS SUCH A SYSTEM:
VERTICAL DISTANCE BETWEEN WASTE BRANCH AND SOIL BRANCH
SHALL NOT BE LESS THAN 20 CM.
IF WB/SINK DIRECTLY CONNECTED TO MAIN STACK THEY SHALL
HAVE 75MM MIN WATER SEAL TRAP FOR BRANCH CONNECTION OF
LESS THAN 75MM DIA OR 50 MM FOR BRANCH CONNECTION MORE THAN
75MM DIA.
8.
9. SYSTEMS MOST PREVALENT IN
WORLD
US - ONE PIPE SYSTEM
SINCE 1934.
UK - ONE PIPE SYSTEM
EUROPE - ONE PIPE SYSTEM
INDIA - TWO PIPE MOSTLY
10. SYSTEM FOLLOWED IN DLF LTD
ONE PIPE SYSTEM SINCE 1997.
OVER 6000 HOUSES CONSTRUCTED
SO FAR.
11. REASONS FOR LOSS OF
TRAP SEAL
INDUCED
SIPHONAGE.
SELF SIPHONAGE.
EVAPORATION.
12. RECOMMENDED DEPTH OF TRAP
SEALS
WATER CLOSETS - 50MM
FLOOR TRAPS - 50MM
FIXTURES CONNECTED DIRECTLY
TO THE STACK WITH BRANCH WASTE
PIPE 75MM DIA AND MORE - 40MM
FIXTURES CONNECTED DIRECTLY WITH
BRANCH WASTE PIPE LESS THAN 75 MM
(ONE PIPE/TWO PIPE SYSTEM) - 40MM
-- DO --(SINGLE STACK/MODIFIED SYSTEM) -
75MM
13. TWO PIPE SYSTEM
ADVANTAGES
ENSURE SEGREGATION OF FOUL SEWAGE FROM WASTE WATER.
NO DANAGER OF BACKFLOW OF SEWAGE IN WASTE FITTINGS
INCASEOF BLOCKAGE OF SOIL PIPE.
ENABLES USE OF WASTE WATER DIRECTLY FOR
IRRIGATION/GARDENING.
SEPARATE WASTE WATER STACK PERMITS ARREST OF SOLIDS
FROM KITCHEN IN THE GULLY TRAP THUS PREVENTING THE FROM
ENTERING SEWER. GULLY TRAPS NEEDS TO BE CLEANED
PERIODICALLY.
DISADVANTAGES
DIFFICULT TO INSTALL IN HIGH RISE BUILDINGS WHERE STACKS
TERMINATE IN SERVICE FLOOR OR IN THE CEILING OF THE BASEMENT.
LONG HORIZONTAL RUNS TO REACH EXTERNAL WALLS /EXTERNAL
SEWERS.
PROVISION OF GULLY TRAP DIFFICULT TO IMPLEMENT IN ABOVE
SITUATION.
REQUIRE MORE SHAFT/DUCT SPACE.
CONGESTED SHAFT RESULTS IN DIFFICULT TO MAINTAIN SYSTEM.
USED IN INDIA AS MATTER OF CONVENTION AND CONSERVATIVE
APPROACH RATHER THAN AS A PRAGMATIC APPROACH.
14. ONE PIPE SYSTEM
ADVANTAGES.
LARGELY REPLACED TWO PIPE SYSTEM IN MOST
DEVELOPED COUNTRIES.
FAST BECOMING PREFERRED SYETEM IN OTHER
PARTS OF THE WORLD.
HIGH QUALITY PIPES,FITTINGS AND INSTALLATION
TECHNIQUES AVAILABLE THESE DAYS.
CONSTANT FLOW OFWATER ENSURES REDUCTION
IN BLOCKAGE PROBLEM.
ELIMINATED GULLY TRAPS. THUS PRECLUDES THE
NEED TO CLEAN THEM.
REQUIRE LESSER SHAFT/DUCT SPACE.
HIGHLY ECONOMICAL IN TERMS OF COST.
QUICK TO CONSTRUCT AND COMMISION.
DISADVANTAGES.
DANGER OF BACK FLOW OF SEWAGE IN WASTE
FITTINGS.
15. FACTORS FAVOURING ONE PIPE SYSTEM
USAGE: LOW- MINIMAL FUs CONNECTED AT EACH FLOOR AND
LOW OCCUPANCY RESULTS IN DIFFICULT TO ENSURE SELF
CLEANSING VELOCITY.
CONSTANT FLOW ENSURES REDUCED BLOCKAGES BY ACHIEVING
OPTIMAL FLOW CONDITIONS ESPECIALLY IN HORIZONTAL
STRETCHES.
SHAFT SPACE IS AT A PREMIUM.
REDUNDANCY - POSSIBLE SINCE NUMBER OF TOILETS
AVAILABLE IN EACH APARTMENT.
BETTER QUALITY OF MATERIALS AND TECHNIQUES AVAILABLE
NOW.
LOW AND EASY MAINTENANCE.
NO STATUTORY EMBARGO. IN FACT BIS CODES PERMITS ONE PIPE
SYSTEM IN HIGH RISE BUILDINGS
PROVEN SYSTEM.
ALL PROBLEMS THAT ARE VISUALISED CAN BE OVER COME.
16. RECOMMENDATIONS
USE 100MM DIA SINGLE STACK SYSTEM UPTO 4
STOREYS.
USE 150 MM DIA SINGLE STACK UPTO 15 STOREYS.
USE 150 MM DIA ONE PIPE SYSTEM BEYOND 15
STROREYS.
COMBINE TWO OR MORE TOILETS AT A FLOOR
WHEREVER POSSIBLE.
USE EWC WITH HORN FOR VENTILATION.
SIMILARLY USE P TRAP/BEND WITH HORN FOR
VENTILATION WHERE EVER POSSIBLE.
EXPLORE USE OF PATENTED SOVENT ONE PIPE
SYSTEM, AIR ADMITTANCE VALVE ETC. TO ENSURE
A VERY HIGH LEVEL OF RELIABILTY.
21. FIXTURE UNITS FOR WATER SUPPLY
S.No TYPE OF FIXTURE FUs SIZE OF INLET IN
MM
1. ABLUTION TAP 1 12
2. BATH TUB/SHOWER 3 15
3. BIDET 3 15
4. SINK AND DRAIN BOARD 3 15
5. DRINKING FOUNTAIN 0.5 9
6. KITCHEN SINK (DOMESTIC) 2 15
7. WASH BASIN 1 9
8. WASH BASIN SURGEONS (OR
FILL AND EMPTY TYPE)
2 15
9. SHOWER (DOMESTIC) 2 15
10. SHOWER (GROUP) 3 15
11. URINAL 4 15
12. WC FLUSH TANK 4 12
13. WC FLUSH VALVE 8 25/32
22. FUs IN JAYPEE GREENS
MASTER TOILET
2 Nos. WHB - 2
WC WITH FLUSH VALVE - 4
SHOWER(DOMESTIC) - 2
BATH TUB - 3
ABLUTION TAP - 1
TOTAL - 12
23. FUs IN JAYPEE GREENS
OTHER TOILETS
WHB - 1
WC WITH FLUSH VALVE - 4
SHOWER(DOMESTIC) - 2
ABLUTION TAP - 1
TOTAL - 8
24. RECOMMENDED SIZES FOR BRANCHES AND VERTICAL STACKS
( IN CASE OF HIGH DISCHARGES SIZE OF THE PIPE SHOULD BE BASED ON THOSE DISCHARGES)
DIA OF PIPE MAX FUs
HOR. BRANCHES STACK OF 3
FLOORS ONE
PER
MORE THAN 3 FLOORS
TOTAL FOR
STACK
TOTAL FOR ONE
BRANCH
32 1 2 2 1
40 3 4 8 2
50 6 10 24 6
75 20 30 60 16
100 160 240 500 90
150 620 960 1900 350
200 1400 2200 3600 600
25. SUGGESTED SYSTEM SELECTION FOR DIFFERENT TYPES OF
BUILDINGS
BY SHRI S.G.DEOLALIKAKR
SER NO. TYPE OF BLDG. TWO
PIPE
SYSTEM
ONE PIPE
SYSTEM
SINGLE
STACK
SYSTEM
HOUSING
A ONE OR TWO STOREYED
SUs, BUNGLOWS
Y Y Y
B. 3-4 STOREYED N Y Y
C. MULTISTOREYED Y Y N
HOSPITAL
D. 2/3 STOREYED FOR
HOSPITAL FIXTURES,
FOR TOILETS
Y
Y
Y
Y
N
Y
E. MULTISTOREYED Y Y N
26. SUGGESTED SYSTEM SELECTION FOR DIFFERENT TYPES OF BUILDINGS BY
SHRI S.G.DEOLALIKAKR
SER NO. TYPE OF BLDG. TWO
PIPE
SYSTEM
ONE PIPE
SYSTEM
SINGLE
STACK
SYSTEM
F. HOUSING, HOSTEL AND
ADMIN BLDG. FOR HOSPITAL
Y Y Y
HOTELS
G. 1/2 STOREYED , BUNGLOWS Y Y Y
H. 3-4 STOREYED N Y Y
I. MULTISTOREYED N Y N
OFFICE BUILDING
J. UP TO 6-8 FLOORS FOR
HOSPITAL FIXTURES,
FOR TOILETS
N Y Y
K. MULTISTOREYED N Y N
27. SYSTEMS FOLLOWED IN JAYPEE GREENS,
GREATER NOIDA
EARTH COURTS - MODIFIED TWO PIPE
SYSTEM. ONLY SOIL PIPE IS VENTILATED.
SEA COURTS/SUN COURTS/CRESCENT
COURTS - TWO PIPE SYSTEM PARTIALLY
VENTILATED ; SOIL AND WASTE PIPE
VENTILATED AT ALTERNATE FLOORS.
ATHLETES HOSTEL - TWO PIPE/STACKS.
ESTATE HOMES/VILLAS – TWO PIPE /STACKS
SYSTEM.
28. RATE ANALYSIS OF VARIOUS SYSTEM
FOR A TYPICAL TOILET
S No.
Item Unit
Average
Qty/t
oilet
Approx
Rate
Cost of One
Pipe
100 mm
stack
Cost of One
Pipe
150mm
stack
Cost of Two
Pipe
Sytem
1 Main Soil and Waste Pipe
100mm dia C.I. as per IS
3989 meter 3.30 1313.50 4334.55 0.00 8,669.10
2 Main Soil and Waste Pipe
150mm dia C.I. as per IS
3989 meter 3.30 1950.00 0.00 6,435.00 0.00
3 Branch soil/waste pipe 100 dia
as per IS: 1729
meter 4.00 1225.00 4900.00 4,900.00 4,900.00
4 ASP 75 mm dia C.I. as per
IS:3989 meter 3.30 1100.00 3630.00 3,630.00 7,260.00
5 Branch vent pipe 50mm dia meter 2.00 750.00 1500.00 1,500.00 0.00
6 Branch inter connection
between ASP and Main
Stack with 50mm dia MS
Pipe meter 2.00 700.00 0.00 0.00 1400
Total Cost per Toilet 14364.55 16,465.00 20,829.10
Percentage savings over two
pipe system
31.04 20.95
29. SIZES OF STACKS
ONE PIPE SYSTEM UP TO 38 STORIES 100 MM
TWO PIPE SYSTEM
-SOIL
-WASTE
UP TO 125 STOREYS
UP TO 62 STOREYS
100 MM
100 MM
SINGLE STACK SYSTEM UP TO 4 STOREYS
UP TO 15 STOREYS
100 MM
150 MM
HORIZONTAL PIPE
- ONE PIPE SYSTEM
- TWO PIPE SYSTEM
- SOIL
- WASTE
UP TO 13 STORIES
14- 52 STORIES
UP TO 40 STORIES
UP TO 20 STRORIES
21 TO 78 STORIES
100 MM
150 MM
100 MM
100 MM
150 MM
30. DESIGN PRINCIPLES
IS-5239-1983: BIS HAS RATIONALISED DESIGN
PROCEDURE IN THE CODE OF PRACTICE FOR
SANITARY PIPE WORK ABOVE GROUND
BUILDINGS.
PIPE SIZE DETERMINED BY ‘FIXTURE UNITS’ ( FUs)
BASED ON EXPERIMENTAL DATA ON VARIOUS
FIXTURES AND USAGE ARRIVED AT BY BIS.
CARRYING CAPACITY OF HORIZONTAL DRAINS IS
SUBSTANTIALLY LOWER. DIA OF VERTICAL
STACKS MAY HAVE TO BE INCREASED DUE TO
REDUCED CAPACITY IN HORIZONTAL STRETCHES.
