BUILDING DRAINAGE

SANITARY SYSTEM

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.

TWO PIPE SYSTEM

ONE PIPE SYSTEM

SINGLE STACK SYSTEM

CHOICE OF PLUMBING SYSTEMAS 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.

CHOICE OF PLUMBING SYSTEMAS 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.

SYSTEMS MOST PREVALENT IN WORLD

US - ONE PIPE SYSTEM SINCE 1934.

UK - ONE PIPE SYSTEMEUROPE - ONE PIPE SYSTEMINDIA - TWO PIPE MOSTLY

SYSTEM FOLLOWED IN DLF LTD

ONE PIPE SYSTEM SINCE 1997.OVER 6000 HOUSES CONSTRUCTED

SO FAR.

REASONS FOR LOSS OF TRAP SEAL

INDUCED SIPHONAGE.

SELF SIPHONAGE.

EVAPORATION.

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

TWO PIPE SYSTEMADVANTAGES

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.

ONE PIPE SYSTEMADVANTAGES. 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.

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.

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.

SOVENT SINGLE STACK DRAINAGE SYSTEM

ProVent PVC SINGLE STACK DRAINAGE SYSTEM

VIEW FROM BELOW THE ROOF SLAB

FIXTURE UNITS FOR WATER SUPPLYS.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

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

FUs IN JAYPEE GREENS

OTHER TOILETS WHB - 1 WC WITH FLUSH VALVE - 4 SHOWER(DOMESTIC) - 2 ABLUTION TAP - 1 TOTAL - 8

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

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

HOUSINGA ONE OR TWO STOREYED

SUs, BUNGLOWSY Y Y

B. 3-4 STOREYED N Y Y

C. MULTISTOREYED Y Y N

HOSPITALD. 2/3 STOREYED FOR

HOSPITAL FIXTURES, FOR TOILETS

YY

YY

NY

E. MULTISTOREYED Y Y N

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

HOTELSG. 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

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.

RATE ANALYSIS OF VARIOUS SYSTEM FOR A TYPICAL TOILET

S No.

Item UnitAverage

Qty/toilet

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  

SIZES OF STACKSONE PIPE SYSTEM UP TO 38 STORIES 100 MM

TWO PIPE SYSTEM -SOIL -WASTE

UP TO 125 STOREYSUP TO 62 STOREYS

100 MM100 MM

SINGLE STACK SYSTEM UP TO 4 STOREYSUP TO 15 STOREYS

100 MM150 MM

HORIZONTAL PIPE- ONE PIPE SYSTEM

- TWO PIPE SYSTEM- SOIL- WASTE

UP TO 13 STORIES14- 52 STORIES

UP TO 40 STORIESUP TO 20 STRORIES21 TO 78 STORIES

100 MM150 MM

100 MM100 MM150 MM

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.