Design Seminar: Plumbing

1. Sneha Nagarajan (10110058)2. Srishti Shubh (10110060)

What is Plumbing?The art and science of creating and maintaining sanitary conditions in buildings

OrThe art and science of installing, repairing and servicing of pipes, fixtures and appurtenances necessary for bringing in water supply, distributing it within and removing the liquid and water-borne wastesIt includes fixtures and fixture traps; soil and waste pipes; vent pipes; building drain and building sewer; storm drainage pipes, their devices, appurtenances and connections to all within or adjacent to the building

Plumbing has been a part of the human race since the dawn of human civilization. Some civilizations saw very sophisticated systems for their time while the services declined marginally during

Earliest plumbing arrangements were unearthed in the Indus Valley Civilization almost 5500years old

Another civilization with highly developed plumbing system was the Egyptian civilization and the Romans. Aqueducts were constructed to carry water from sources to houses. Extensive underground sewage systems. Public baths.

Sanitary systems declined after the Romans and AD476 and only around the 1500’s to 1800’s were concerns raised for better sanitary systems!

Indus Valley Civilization: Drainage System

Roman Bath: Thermae

Roman AqueductsRoman Lead Pipes:With a folded seam

The Basic Plumbing Components of any building:

1. Water supply distributing pipes2. Fixture and fixture traps3. Soil, waste and vent pipes4. Storm water drainage

NBC GENERAL REQUIREMENTS for design considerations: •Smooth joints •Avoid noise transmission •Avoid formation of air locks •Avoid unsightly arrangement •Economy in labour and materials •No piping under wastewater pipes •Gradual size and direction changes •Maximum rate of discharge required •Water-tight pipes and pipe-connections •No back-flow towards the source of supply •Wholesome water supply for drinking and culinary purposes •No direct connection of boilers or hot machinery, use feed cistern •No cross-connection between pure and contaminated water pipes •Sufficient strength of pipes underground or under traffic loads or frost •Maintain definite air gap in all appliances (minimum 15 cm or twice pipe bore for storage cisterns) •Corrosion protection measures in corrosive environments (e.g. corrosive soils, proximity to electric cables), e.g. exterior CI tubing

Supply System

3.1.1 Potable WaterAll premises intended for human habitation, occupancy, or use shall be provided with supply of potable water. This water supply shall not be connected with unsafe water resources, nor shall it be subject to the hazards of backflow.

3.1.2 Water ProvisionPlumbing fixtures, devices and appurtenances shall be provided with water in sufficient volume and at pressures adequate to enable them to function properly and without undue noise under normal conditions of use.There should beat least a residual head of 0.018 N/mm2 at the consumer’s tap.NOTE—The residual head shall be taken at the highest farthest outlets in the building.

3.1.14 MaintenancePlumbing systems shall be maintained in a safe and serviceable condition.

3.1.15 AccessibilityAll plumbing fixtures shall be so installed with regard to spacing as to be accessible for their intended use and for cleaning. All doors, windows and any other device needing access within the toilet shall be so located that they have proper access.

4.1.1 Water Supply for ResidencesA minimum of 70 to 100 litres per head per day may be considered adequate for domestic needs of urban communities, apart from non-domestic needs as flushing requirements. As a general rule the following rates per capita per day may be considered minimumfor domestic and non-domestic needs: NOTE— The value of water supply given

as 150 to 200 litres per head per day maybe reduced to 135litresper headper day for houses for Lower Income Groups (LIG) and Economically Weaker Section of Society(EWS),depending upon prevailing conditions.

4.1.1.1 Out of the 150 to 200 litres per head per day, 45 litres per head per day may be taken for flushing requirements and the remaining quantity for other domestic purposes.

4.3.1.1 For residential buildings, the requirements ofwater shall be based on the actual number of occupants;where this information is not available, the number ofoccupants for each residential unit may be based on afamily of five. For assessing the population in otheroccupants, reference may be made to Part 4 ‘Fire andLife Safety’.

4.1.2 Water Supply for Buildings Other than Residences

The NBC states several codes for plumbing needs of buildings of various other uses. Refer Section 4.1 of part9 for the same.

4.1.4 Water Supply for Fire Fighting Purposes4.1.4.1 The Authority shall make provision to meetthe water supply requirements for fire fighting in theCity/area, depending on the population density andtypes of occupancy.4.1.4.2 Provision shall be made by the owner of thebuilding for water supply requirements for fire fightingpurposes within the building, depending upon theheight and occupancy of the building, in conformitywith the requirements laid down in Part 4 ‘Fire andLife Safety’.4.1.4.3 The requirements regarding water supply instorage tanks, capacity of fue pumps, arrangements ofwet riser-cum-downcomer and wet riser installationsfor buildings above 15 m in height, depending uponthe occupancy use, shall

Water Sources and Quality: The NBC guidelines lay out the rules to ensure water quality at the various stages of supply and consumption and disposal. Potable or for other purposes. Fresh water sources: lakes/rivers. Waste water reclamation

4.4 Storage of Water4.4.1 In a building, provision is required to be made for storage of water for the following reasons:a) to provide against interruptions of the supply caused by repairs to mains, etc;b) to reduce the maximum rate of demand on the mains;c) to tide over periods of intermittent supply; andd) to maintain a storage for the fire fighting requirement of the building (see Part 4 ‘Fireand Life Safety’ ).

There are clear guidelines as to what material is to be used for various uses and their design considerations.While designing we need to keep in mind the design of1. Manholes2. Catch rings and ladders3. Overflow pipes4. Vent pipes5. Scour pipes6. Connections to these7. Tanks

4.4.10 The quantity of water to be stored shall be calculated taking into account the following factors:a) hours of supply at sufficiently high pressure to fill up the overhead storage tanks;b) frequency of replenishment of overhead tanks, during the 24 h;c) rate and regularity of supply; andd) consequences of exhausting storage particularly in case of public buildings like hospitals.

Calculation of Drain/Trap Diameter:

fu

Calculated length (measured length + 1/2 measured length) = 90 + 45 = 135'

flow

make a table that shows the

Measured length of system (origin to farthest fixture) = 90'

60 p.s.i.

Availablepressure =

max. gpm for each pipe size:max gpm3 1/21018284478

3/4"

1 1/2"2"

1 1/4"1"

pipe dia.1/2"

gpm20

12'

Using the pipe size chart

to no faster than 8 feet / sec.water through the pipingLimit the velocity of

x 100 = 23.46 psi / 100'

The available pressure in psi per 100'31.67'135'

2

WaterMeter

rise pressure loss = 4.33 psifixture pressure loss = 15 psi

meter pressure loss = 9 psi

total pressure loss =

Available pressure of 60 psi, minus

to push the water through the system.28.33 pressure loss = 31.67 psi

28.33 psi

6'

flow

system

rise

s 10'

flowfu30flo

w

10

unitsfixture

gpm 8 10

gpm20fu30

8' 10'

flow

gpm14fu20

gpm7fu8 flow

12

6'

fu 9 gpm

unitsfixture

8

WATER SUPPLY EXERCISEPLUMBING

total fixture units = 30 = 20 gpm

longest length = 90'

unitsfixture

12

50'

System is predominately flush TANKS

4.7 Distribution Systems in Multi-Storeyed Buildings4.7.1 There are four basic methods of distribution of water to a multi-storeyed buildings.1. Direct supply from mains to ablutionary taps and kitchen with WCs and urinals supplied by overhead tanks.2. Direct Pumping Systems3. Hydro-Pneumatic Systems4. Overhead Tanks Distribution

4.7.2 Direct Supply SystemThis system is adopted when adequate pressure is available round the clock at the topmost floor. With limited pressure available in most city mains, water from direct supply is normally not available above twoor three floors.

4.7.3 Direct PumpingWater is pumped directly into the distribution system without the aid of any overhead tank, except for flushing purposes. The pumps are controlled by a pressure switch installed on the line.

4.7.4 Hydro-Pneumatic SystemsHydro-pneumatic system is a variation of direct pumping system. An air-tight pressure vessel is installed on the line to regulate the operation of the pumps. The vessel capacity shall be based on the cut-in and cut-out pressure of the pumping system depending upon allowable start/stops of the pumping system. The system shall have reliable power supply to avoid breakdown in the water supply.

4.7.5 over-head Tank Distribution4.7.5.1 This is the most common of the distribution systems adopted by various type of buildings.4.7.5.2 The system comprises pumping water to one or more overhead tanks placed at the top most location of the hydraulic zone.4.7.5.3 Water collected in the overhead tank is distributed to the various parts of the building by a set of pipes located generally on the terrace.

Plumbing Fittings

various types

STANDARD PIPE FITTINGS( FRINGES )

couplingstandard

inline tee

flowwater

valve of

flowwater

90 degreestandard ell

45 degreestandard ell

flowwater

flow

side tee90 degree

flowwater

water

flowwater

GLOBE VALVE GATE VALVE

ANGLE VALVECHECK VALVE

Plumbing Fixtures

3.1.5 Plumbing FixturesIt is recommended that each family dwelling unit should have at least one water closet, one lavatory, one kitchen wash place or a sink, and one bathing wash place or shower to meet the basic requirements of sanitation and personal hygiene.

3.1.8 Fixture Traps and Vent PipesEach fixture directly connected to the drainage system shall be equipped with a liquid seal trap, Trap seals shall be maintained to prevent sewer gas, other potentially dangerous or noxious fumes, or vermin from entering the building. Further, the drainage system shall be designed to provide an adequate circulation of air in all pipes with no danger of siphonage, aspiration, or forcing of trap seals under conditions of ordinary use by providing vent pipes throughout the system.

Drainage System

3.1.6 Drainage SystemThe drainage system shall be designed, installed and maintained to guard against fouling, deposit of solids and clogging and with adequate cleanouts so arrangedthat the pipes may be readily cleaned.

3.1.9 Foul Air ExhaustEach vent terminal shall extend to the outer air and be so installed as to minimize the possibilities of clogging and the return of foul air to the building, as it conveys potentially noxious or explosive gases to the outside atmosphere. All vent pipes shall be provided with a cowl.

Drainage Installation

• Soil and Waste Drainage System- Two-pipe Ventilated Gravity System- U/G Petrol Interceptor for Carpark- Discharge to Public Foul Water System

• Storm Water Drainage System- Rain Water Outlet at Roof, Balcony & Canopy- Discharge to Public Storm Water System

CASE STUDIES

STUDY OF PLUMBING SYSTEM OF A TYPICAL 2 BHK APARTMENT BUILDING

BATH/WC. (DETAIL A)

KITCHEN (DETAIL B)

DUCTS

DETAIL OF BATH/ WC. AND KITCHEN SINK WATER SUPPLY AND DRAINAGE SYSTEM AND SCHEDULE OF FIXTURES AND FITTINGS

INSPECTION CHAMBERS

DETAIL OF EXTERIOR DRAINAGE CONNECTION AND SCHEDULE OF MATERIALS

TERRACE PLAN SHOWING FLOOR PLATE SLOPE

RAINWATER PIPE100 dia.

POSITIVES:• Intelligent placing of Ducts and Wet areas to facilitate easy outflow and maintenance.• Separation of Toilet and Kitchen sewage lines for separate drain out into respective

pipelines.• Separate Water Supply pipes for Domestic and Flushing purposes.• Rainwater pipes are place in appropriate corners, having maximum catchment

area, reducing number of pipes required.• New-age flush and tap systems used.• Pipework hidden from plain view in elevation with the help of extruded Chajjas and

Elevation Fins.• No overlap of Bathrooms with bedrooms or kitchen between levels.• Toilets ventilated into ducts, preventing escape of foul smell to Living areas.

NEGATIVES:• No provision for Hot water supply in Bathrooms and Kitchen.• Door clearance for WCs not standard.

CITY OF MILWAUKEE CROSS CONNECTION PROGRAM

Milwaukee is the largest city in the U.S. state of Wisconsin. It is located on the south-western shore of Lake Michigan.

Map and Location of Milwaukee City

WHAT IS BACK FLOW?

In water supply systems, water is normally maintained at a significant pressure to enable water to flow from the tap, shower etc.

When pressure fails or is reduced, (as may happen if a water main bursts, pipes freeze or there is unexpectedly high demand on the water system), then such reduced pressure in the pipe may allow contaminated water from the ground, from storage or from other sources to be drawn up into the system.

WHAT IS CROSS CONNECTION?

Cross-connections, are defined as actual or potential connections between a potable water supply and a non-potable source, where it is possible for a contaminant to enter the drinking water supply.

STATISTICS:• Approximately 15,800 commercial water accounts serve buildings in Milwaukee.

• The Plumbing Inspectors developed a reference manual identifying the various types of cross connection configurations and the proper cross connection control devices to correct them.

Typical Cross Connections:

Apartments- Laundry Tub Faucets- Hose Faucets- Boilers

Office Buildings- Boilers- Chillers- Soap Dispensers- Water Closets- Coffee Makers

Restaurants- Beverage Dispensers- Food Grinders- Steamer- Dishwasher- Glass Washer- Soap Dispenser- Hose and Spray

Manufacturing Plants - Chemical Dispensers

- Cooling Towers - Boilers

- Hose Faucets- Equipment using Potable Water

MILWAUKEE DRAINAGE SYSTEM

Janitors Faucet

Laundry Tub Faucets

Hose and Spray

Hose and Spray

Fill Valve

Boilers

Electric Boiler

Cooling Towers

Coffee Makers

Carbonator

Carbonator

Soap Dispenser

Commercial Dishwasher

Parts Washer

Chemical Dispenser

CORRECTIVE MEASURES APPLIED:

• Hose thread vacuum breakers were installed.• A licensed plumber working under a permit is required for any other form of

cross connection correction.

Hose Bibb

Hose Bibbs – Medical Whirlpool

Backflow Preventer

BUILDING SERVICES INSTALLATIONS

Reliability

Design Intent

New TechnologyFlexibility

Health & Safety

Maintainability

Energy Efficiency

Sustainability

Sanitary Plumbing System Enclosed in Fire-Rated Service Duct

Service duct

Sanitary stack

Cleaning Eye

Central Building Plan Unit 30.11.1999

Sanitary Plumbing over Bed / Living / Dining Rooms and Kitchen

Clarification• Pipe leakage and maintenance work would

pose nuisance conditions and inconvenience to owners of lower level strata units.

• Sanitary pipes shall be routed away from such places.

• Maintenance duct with access taken from common areas shall be provided if dry areas cannot be avoided.

Common ErrorIn buildings under Land Titles (Strata) Act, sanitary pipes are sited over bedrooms, living room, dining room or kitchen of the strata unit below.

Details of Double Floor Slab / Maintenance Duct

Sanitary Plumbing over Bed / Living / Dining Rooms and Kitchen

Sanitary Plumbing over Water Tanks / Transformer / Switchgear

Clarification• Sanitary pipes shall not be

located over water tanks, transformer, switchgear or other places where it can cause health and safety hazards.

Common Error • Sanitary pipes sited over water tanks, transformer and switchgear

•Leaks from sanitary pipes could contaminate water tanks etc.

Sanitary Plumbing over Water Tanks / Transformer / Switchgear

Water Tank

Sanitary Pipe

Ventilation Stack Terminating at Roof Level

Common ErrorVentilation stacks terminate at communal or private roof terrace / garden causing foul odour nuisance to residents.

ClarificationVentilation stack shall terminate at the highest roof level and shall be sited in common service areas outside private roof terraces / gardens.

This will facilitate maintenance work and minimise inconvenience and nuisance to occupants.

To avoid vent pipes terminating in the private roof terraces / gardens, the vent pipe may be offset and extended for termination at the highest point of the building or other suitable location that will not cause smell nuisance or health hazard to the occupants.

Design Considerations for Sewerage

Sewer Connection

Clarification• In general, only one sewer

connection is permitted per development.

• This is to minimise • number of road openings• inconvenience to

neighbouring properties when public sewer is located in adjacent property

• disruption to sewerage system due to interruption of sewage flow

Common issueCan a development have more than one sewer connection?

Sewer Connection

Clarification• Existing sewer connection shall be re-

used whenever possible. • Where a new sewer connection is

required because of development layout, it is necessary to obtain written consent from the owner of adjacent lot.

Common IssueCan a new connection be provided for a development if the existing sewer is located in neighbouring property?

Sewer Connection

Clarification• Builder shall pre-consult authorities

for all subdivision cases.• This is to safeguard sewer

connection for the sub-divided land parcels.

• Existing drainline / sewer within the subdivided plots shall not be abandoned / diverted without written approval.

Common IssueSewer connection affected by subdivision of land

Energy Conservation

• Locate hot water heater in conditioned space• Insulate hot water heater• Insulate exposed hot water pipes• Insulate cold water pipes with freezing potential• Place water pipes in interior walls, if possible• Use low-flow fixtures• Seal all wall fenestrations through which pipes run

Albert Einstein was named an honorary member of the Plumbers and Steamfitters Union after publicly stating that he would become a plumber if he had to do it all over again!

“If I could do it all again, I'd be a plumber.”

References:1. National Building Code2. Daisariya Architects, Mumbai Pvt Ltd3. www.mmsd.org

THANK YOU!