Code of practice for water supply in buildings

IS 2065 - Scope: Key Formulas, Tables & Specifications

Scope covers water supply pipe sizing, fittings, and plumbing work requirements including applications and certifications.

Key Formulas & Tables

1. Hazen-Williams Equation (Appendix C, Clause 5.4.2)

Used for estimating friction loss in water pipes:

[ h_f = 10.67 \times \frac{L}{C^{1.85} \times d^{4.87}} \times Q^{1.85} ]

• (h_f) = head loss (m)
• (L) = length of pipe (m)
• (d) = internal diameter (m)
• (Q) = flow rate (litres/sec)
• (C) = Hazen-Williams roughness coefficient (typically 100 for GI pipes)

Nomogram (Fig. 2) provided for quick friction loss and pipe diameter selection.

2. Application & Certification Forms (Appendix A & B)

• Application for water supply specifying premises, purpose, and flow requirements.
• Licensed plumber’s completion certificate for plumbing work verification.

Additional Notes

• Use standard pipe sizes closest to design size.
• Refer IS 2951 (Parts 1 & 2) for universal pipe friction diagrams.
• Temperature and viscosity variations affect flow but are simplified by Hazen-Williams empirical formula.

flowchart LR
    A[Application for Water Supply] --> B[Licensed Plumber's Work]
    B --> C[Completion Certificate]
    C --> D[Authority Inspection & Approval]
    D --> E[Water Connection Granted]

Summary: IS 2065 provides application procedures, plumbing certification, and uses Hazen-Williams formula for pipe sizing and friction loss estimation with nomograms for practical design.

IS 2065: Definitions & Key Formulas Summary

Definitions (Clause 2.0)

• Standard definitions related to water supply, drainage, and sanitation apply.
• Terms like flow regimes (laminar, turbulent), pipe roughness, and Reynolds number are fundamental.

Key Formula: Hazen-Williams Equation (Appendix C, Clause 5.4.2)

Used for estimating head loss due to friction in pipes:

[ h_f = 10.67 \times \frac{L}{C^{1.85} d^{4.87}} Q^{1.85} ]

Where:

• (h_f) = head loss (m)
• (L) = pipe length (m)
• (d) = internal pipe diameter (m)
• (Q) = flow rate (litres/sec)
• (C) = roughness coefficient (typically 100 for GI pipes)

Nomogram (Fig. 2)

• Graphical tool to find friction loss, velocity, or pipe diameter for given flow and head loss.
• Example: For 25 mm GI pipe, 0.25 l/s flow, 300 m length, friction loss = 9 m.

Additional Notes:

• Reynolds number and flow pattern influence formula choice.
• IS 2951 (Parts 1 & 2) provide universal pipe friction diagrams.
• Application and certification forms (Appendices A & B) standardize water supply connections.

flowchart LR
    A[Flow Rate Q] --> B[Calculate Reynolds Number]
    B --> C{Flow Regime}
    C -->|Laminar| D[Use Laminar Flow Formula]
    C -->|Turbulent| E[Use Hazen-Williams Equation]
    E --> F[Calculate Head Loss hf]
    F --> G[Select Pipe Diameter & Length]

Summary: Use Hazen-Williams for practical head loss calculations; refer to nomograms for quick estimations. Definitions clarify flow regimes and parameters used in design.

IS 2065: General Principles - Key Points & Formulas

Basic Principles (Clause 7.1)

• Sanitary and safety principles govern plumbing design.
• Details may vary, but principles guide unforeseen situations.
• Proper design, installation, and maintenance are essential.

Application & Certification (Appendices A & B)

• Formal application for water supply or alterations.
• Licensed plumber must carry out work.
• Completion certificate by plumber and authority inspection required.

Hydraulic Design (Clause 5.4.2 & Appendix C)

• Use Hazen-Williams formula for friction loss in pipes:

  [ h_f = 10.67 \times \frac{L}{C^{1.85} \times d^{4.87}} \times Q^{1.85} ]

  where:

  • ( h_f ) = head loss (m)
  • ( L ) = pipe length (m)
  • ( d ) = diameter (m)
  • ( Q ) = flow rate (m³/s)
  • ( C ) = Hazen-Williams roughness coefficient (typically 100 for GI pipes)

• Nomogram provided in Appendix C simplifies head loss and diameter selection.

Materials & Layout (Clause 8.1)

• Follow general principles for pipe layout and planning.
• Use standard pipe sizes from commercial availability.
• Account for temperature effects on water viscosity.

flowchart LR
    A[Water Supply Application] --> B[Licensed Plumber]
    B --> C[Plumbing Work Execution]
    C --> D[Completion Certificate]
    D --> E[Authority Inspection]
    E --> F[Connection Approval]

Summary:
Use Hazen-Williams formula/nomogram for hydraulic design, ensure licensed plumber involvement, apply sanitary principles, and follow prescribed application and certification procedures.

IS 2065 - Materials for Pipes and Fittings: Key Points

1. Materials for Pipes (Clause 6.2)

Pipes can be made from:

• Cast Iron: Vertically cast or centrifugally cast
  (See IS:1536-1976, IS:1537-1976)
• Steel: Bitumen-lined/coated, optionally with cement concrete coating
  (See IS:1916-1963, IS:3589-1966)
• Reinforced Concrete:
  (See IS:458-1971)
• Prestressed Concrete:
  (See IS:784-1978)
• Mild Steel Tubes (Galvanized):
  (See IS:1239 Part 1-1979)
• Copper:
  (See IS:1545-1982)
• Brass:
  (See IS:407-1981)
• Wrought Iron
• Asbestos Cement:
  (See IS:1626-1960, IS:1592-1980)
• Lead:
  (See IS:404 Part 1-1977)
• Polyethylene:
  (See IS:3076-1968, IS:4984-1978)
• Unplasticized PVC:
  (See IS:4985-1981)

2. Flow Estimation & Head Loss (Clause 5.4.1 & 5.4.2)

• Hazen-Williams Formula is recommended for water flow in pipes of smaller sizes:

  [ V = k \cdot C \cdot R^{0.63} \cdot S^{0.54} ]

  Where:

  • (V) = velocity (m/s)
  • (C) = Hazen-Williams roughness coefficient (depends on pipe material)
  • (R) = hydraulic radius (m)
  • (S) = slope of energy grade line (head loss per length)
  • (k) = unit conversion factor (usually 0.85 for SI units)

• Nomograms and charts based on Hazen-Williams are in Appendix C of IS 2065.

• For detailed friction loss, refer to IS:2951 (Part

IS 2065 - Design and Sizing of Pipes: Key Points

1. Design Data Required (Clause 5.3.1)

• Maximum discharge rate (Q)
• Pipe length (L)
• Head loss by friction (h_f)
• Pipe internal roughness

2. Head Loss Calculation

• Use Hazen-Williams formula for water supply pipes (small sizes, practical accuracy):

[ h_f = 10.67 \times \frac{L}{C^{1.85} \times d^{4.87}} \times Q^{1.85} ]

Where:

• (h_f) = head loss (m)
• (L) = pipe length (m)
• (d) = internal diameter (m)
• (Q) = flow rate (m³/s)
• (C) = Hazen-Williams roughness coefficient (typically 130-150 for new pipes)

3. Nominal Diameter

• Use nominal internal diameter as per Clause 2.22 for sizing.

4. Empirical & Rational Methods

• For more accuracy, use Reynolds number-based formulas and friction factor charts (IS 2951 Part 1 & 2).
• Allow for losses in fittings (bends, valves) as per IS 2951 (Part 2).

5. Appendix C

• Contains Hazen-Williams nomogram for quick sizing.

Summary Table: Hazen-Williams Roughness Coefficients (Typical)

flowchart LR
    A[Determine Q, L, h_f, pipe roughness] --> B[Select nominal diameter d]
    B --> C[Calculate head loss using Hazen-Williams]
    C --> D{Is h_f acceptable?}
    D -- Yes --> E[Finalize pipe size]
    D -- No --> B

**Use IS 2065 Clause 5.4.2 and Appendix C for practical sizing

Installation Practices per IS 2065 (Relevant Clauses)

1. Design & Sizing (Clause 5.4.2 & Appendix C):

• Use Hazen-Williams formula for friction loss estimation in water pipes:
  [ h_f = 10.67 \times \frac{L}{C^{1.85} \times d^{4.87}} \times Q^{1.85} ] where:

  • (h_f) = head loss (m)
  • (L) = pipe length (m)
  • (C) = Hazen-Williams roughness coefficient (typ. 100 for GI pipes)
  • (d) = internal diameter (m)
  • (Q) = flow rate (m³/s)

• Use Nomogram (Appendix C) for quick friction loss and diameter selection.

2. Fixing Spacing (Clause 9.10 & Appendix F):

• Pipes must be fixed at regular intervals (refer Appendix F for spacing values).
• Typical GI pipe fixing spacing:
  • Horizontal runs: 1.5 to 2 m
  • Vertical runs: 1.0 to 1.5 m

3. Jointing (Clause 6.2.4):

• Follow specific standards for pipe types:
  • Asbestos Cement Pipes: IS 6530-1972
  • Mild Steel Tubes: IS 3589 (Part 1)
  • Lead Pipes: IS 4432 (Part 1)
  • PVC Pipes: IS 4985
  • HDPE Pipes: IS 14333

Summary Table: Fixing Spacing (Typical Values)

flowchart LR
    A[Water Supply Design] --> B[Calculate Flow Q]
    B --> C[Select Pipe Diameter d

IS 2065 Key Points: Plumbing Details & Safety Principles

Basic Principles (Clause 7.1)

• Plumbing must be properly designed, installed, and maintained.
• Sanitary and safety principles remain consistent regardless of construction variations.
• Principles guide unforeseen situations not explicitly covered.

Water Flow & Pipe Sizing (Clause 5.4.2 & Appendix C)

• Use Hazen-Williams formula for friction loss in pipes (nomogram provided).
• Hazen-Williams equation (empirical):

[ h_f = 10.67 \times \frac{L}{C^{1.85} \times d^{4.87}} \times Q^{1.85} ]

Where:

• (h_f) = head loss (m)

• (L) = pipe length (m)

• (d) = pipe diameter (m)

• (Q) = flow rate (m³/s)

• (C) = roughness coefficient (typically 100 for GI pipes)

• Use nomogram (Fig. 2 in Appendix C) to find friction loss or pipe size quickly.

Materials & Certification (Clause 6 & Appendices A, B)

• Applications for water supply must be submitted with details of premises and water requirements.
• Licensed plumbers must certify completion of plumbing work.
• Authorities inspect and approve installations ensuring compliance with safety and sanitary standards.

Summary Diagram: Plumbing System Flow

flowchart TD
    A[Water Source] --> B[Service Pipe]
    B --> C[Water Meter]
    C --> D[Distribution Pipes]
    D --> E[Fixtures & Appliances]
    E --> F[Drainage & Waste Disposal]

Safety & Sanitary Essentials:

• Proper drainage to avoid contamination.
• Use licensed plumbers.
• Follow local bylaws and IS code requirements.
• Regular maintenance to prevent leaks and blockages.

For detailed pipe sizing, refer to Appendix C nomogram and IS 2951 for friction loss charts.

IS 2065 - Pipe Work Layout and Planning: Key Points

1. General Principles (Clause 8.1)

• Layout must ensure efficient flow, accessibility for maintenance, and minimize head loss.
• Use standard pipe sizes matching design requirements.
• Consider temperature effects on water viscosity and flow.

2. Flow Estimation (Clause 5.4.2 & 5.4.1)

• Hazen-Williams formula is recommended for water supply pipes, especially small sizes.
• Nomograms for Hazen-Williams are provided in Appendix C.
• For more accurate flow and head loss, use Reynolds number-based methods and friction diagrams from IS 2951 (Part 1 & 2).

Hazen-Williams formula:

[ V = k \times C \times R^{0.63} \times S^{0.54} ]

Where:

• (V) = velocity (m/s)
• (C) = Hazen-Williams roughness coefficient (typical 100-140)
• (R) = hydraulic radius (m)
• (S) = slope of hydraulic grade line
• (k) = constant (usually 0.85 for SI units)

3. Fixing Spacing (Clause 9.10)

• Follow Appendix F for recommended fixing intervals to avoid pipe sagging and vibration.

4. Materials & Jointing (Clause 6 & 10)

• Use materials and fittings as per IS specifications.
• Jointing methods must ensure leak-proof and durable connections.

flowchart LR
    A[Design Flow & Pressure] --> B[Select Pipe Size]
    B --> C[Apply Hazen-Williams Formula]
    C --> D[Check Head Loss & Velocity]
    D --> E[Plan Layout for Accessibility & Fixings]
    E --> F[Select Materials & Joints]
    F --> G[Installation & Testing]

Summary: Use Hazen-Williams for sizing, IS 2951 for friction loss, follow fixing spacing in Appendix F, and ensure proper materials and jointing per IS 2065.

IS 2065 Key Points on Excavation, Laying & Jointing of Pipes

Excavation & Bedding (Clause 9.1 & 9.1.1)

• Trench Bottom: Must be firm, level, and true to line & gradient.
• Width: Sufficient for pipe laying and jointing; joint holes where needed.
• Bedding: Pipes must rest fully on a firm surface.
• Refilling: Surround pipes with fine selected material, well rammed; no stones in contact.
• Rock Excavation: Provide a layer of fine material or concrete bedding under pipes.

Laying of Pipes (Clause 9.2.2)

• Follow IS 783-1959 for Concrete Pipes.
• Follow IS 3114-1965 for Cast Iron Pipes.

Jointing of Pipes (Clause 10)

• Joint holes made where necessary.
• Use proper jointing methods as per pipe type standards.

Fixing Spacing (Clause 9.10)

• Internal pipe fixings spaced per Appendix F (typically 1.5–2 m for steel pipes).

Typical Bedding Detail (Simplified)

graph TD
    A[Trench Bottom] --> B[Layer of Fine Selected Material or Concrete Bedding]
    B --> C[Pipe Barrel Fully Supported]
    C --> D[Surround Pipe with Fine Material, Well Rammed]
    D --> E[Backfill with Selected Material, No Stones in Contact]

Summary Table: Bedding & Backfill

For detailed jointing methods and laying practices, refer directly to IS 783 and IS 3114 standards.

IS 2065 Key Points on Specific Pipe Types and Jointing Methods

1. Pipe Jointing Methods (Clause 10.1.5 & 10.1.6)

• Small diameter pipes (wrought iron, steel, cast iron): Use copper-alloy screwed unions or ferrules.
• Large diameter pipes: Use flanged connecting pieces for joints.
• Flexible joints for cast iron pipes: Allowed only with manufacturer's approval and strictly per instructions.

2. Fixing Spacing for Internal Piping (Clause 9.10)

• Fixings must be spaced at regular intervals as per Appendix F (refer to IS 2065 Appendix F for exact spacing values based on pipe diameter).

3. Hydraulic Design (Clause 5.4.2)

• Use Hazen-Williams formula for flow calculations in water supply pipes:

  [ V = k \cdot C \cdot R^{0.63} \cdot S^{0.54} ]

  Where:

  • (V) = velocity (m/s)
  • (C) = Hazen-Williams coefficient (depends on pipe material)
  • (R) = hydraulic radius (m)
  • (S) = slope of hydraulic grade line
  • (k) = constant (usually 0.849 for SI units)

• Refer to Appendix C for nomograms and charts.

Summary Table of Jointing Methods

flowchart TD
    A[Pipe Diameter & Type] --> B{Diameter < 100 mm?}
    B -- Yes --> C{Pipe Type?}
    C -- Wrought Iron/Steel or Cast Iron --> D[Use Copper-alloy Screwed Unions/Ferrules

IS 2065 Key Points on Storage Tanks & Valves

Storage Tanks (Clause 11.3, 11.2.1)

• Tanks must be watertight, covered with a dust, light, mosquito-proof lid with lock.
• Made of galvanized steel sheets (welded, riveted, or pressed). Thickness varies by tank depth.
• Rectangular pressed steel tanks: 120 cm square typical, conforming to IS 804-1967.
• Internal coating: bituminous or suitable non-taste/odor imparting material.
• Lead-lined tanks prohibited.

Ball Valves (Clause 11.3)

• Must conform to IS 1703-1977 (horizontal plunger type with float).
• Positioned so valve body never submerges when full.
• Water level limited to 25 mm below overflow/warning pipe lip.

Stop Valves (Clause 11.5)

• Full-way gate valves preferred.
• Provided at every outlet except overflow pipes.
• Stop valve also on inlet for maintenance.

Warning Pipes (Clause 11.4)

• Mosquito-proof, visible outlet.
• Outlet ≥ 60 cm above any drain/sink/gully.
• No direct sewer/drain connection.
• Union bore ≥ 20 mm, bottom pipe ≥ 25 mm above water level.
• Water level set 25 mm or pipe diameter below overflow/warning pipe.

Summary Table:

flowchart

IS 2065 - Use of Valves: Key Points & Formulas

1. Ball Valves (Clause 12.7)

• Types: High pressure or Low pressure.
• Must conform to IS: 1703-1977.
• Used for controlling flow in pipelines.

2. Flow Measurement (Clauses 5.4.1 & 5.4.2)

• Flow depends on Reynolds number, pipe roughness, and flow pattern (laminar, turbulent).
• Use IS: 2951 (Part 1 & 2) - 1965 for pipe friction diagrams.
• Hazen-Williams formula recommended for water supply pipes (empirical but reliable for small sizes).

Hazen-Williams Formula:

[ h_f = 10.67 \times \frac{L}{C^{1.85} \times d^{4.87}} \times Q^{1.85} ]

Where:

• (h_f) = head loss (m)
• (L) = pipe length (m)
• (d) = internal diameter (m)
• (Q) = flow rate (m³/s)
• (C) = Hazen-Williams roughness coefficient (typical: 100 for GI pipes)

3. Nomogram (Appendix C)

• Used for quick estimation of friction loss and pipe sizing.
• Example: For 25 mm GI pipe, 0.25 l/s, 300 m length → friction loss = 9 m.

Summary Table: Valve & Flow Parameters

flowchart LR
    A[Water Supply] --> B[Pipe]
    B --> C{Valve}
    C -->|Ball Valve| D[IS: 1703]
    B --> E[Flow Measurement]
    E --> F[Reynolds Number]
   

IS 2065 - Disinfection of Storage Tanks and Pipes (Clause 13.2)

Key Specifications & Procedure:

• Initial flushing: Fill tanks and pipes with water; flush thoroughly.
• Disinfection dose: Add chlorine to achieve 50 ppm (parts per million) chlorine concentration.
• Bleaching powder dosage:
  • 150 g bleaching powder per 1000 liters (1 m³) water.
  • Powder mixed to creamy consistency before adding.
• Filling & mixing: Add chlorine gradually while filling for uniform mixing.
• Flushing taps: Open taps progressively away from tank; close each when chlorine smell is detected.
• Contact time: Keep tanks and pipes charged with chlorinated water for at least 3 hours.
• Final flushing: Thoroughly flush before domestic use.

Summary Table:

Additional Notes:

• Proprietary chlorine chemicals: Follow manufacturer’s recommended dosage.
• Annual cleaning of tanks and pipes recommended.
• Corroded tanks: Wire brush, clean, and coat with inert anti-corrosive paint (Clause 15.1).
• Disinfection method subject to authority approval (Clause 13.1).

flowchart TD
    A[Fill tank with water] --> B[Flush thoroughly]
    B --> C[Add chlorine gradually to get 50 ppm]
    C --> D[Fill tank completely]
    D --> E[Open taps progressively until chlorine smell detected]
    E --> F[Close taps and top up tank with chlorinated water]
    F --> G[Keep charged for 3 hours]
    G --> H[Flush tank and pipes before use]

This ensures safe, potable water supply free from microbial contamination as per IS 2065 standards.

IS 2065: Inspection and Testing - Key Points

1. Inspection Before Delivery (Clause 14.1)

• Pipes, fittings, and appliances must bear the ISI certification mark or testing authority mark.
• Factory hydraulic testing at 2× maximum permissible working pressure or higher.
• On-site inspection includes sounding pipes to detect cracks.
• Defective items must be marked rejected and removed immediately.

2. Hydraulic Test Pressure

[ P_{test} = 2 \times P_{working} ]

Where:

• (P_{test}) = Test pressure
• (P_{working}) = Maximum permissible working pressure

3. Disinfection of Storage Tanks and Pipes (Clause 13.2)

• Fill and flush tanks/pipes thoroughly with water.
• Add chlorine disinfectant to achieve 50 ppm chlorine concentration.
• For bleaching powder:
  [ 150,g \text{ powder} / 1000,L \text{ water} ]
• Keep charged for minimum 3 hours.
• Flush thoroughly before use.

4. Relevant IS Specifications for Materials

• IS 6530: Laying of asbestos cement pipes
• IS 14885: Prestressed concrete pipes
• IS 1239 (Part 1): Mild steel tubes
• IS 3589: Lead pipes
• IS 4984: PVC pipes for potable water
• IS 7328/ IS 10146: HDPE/LDPE pipes for potable water

flowchart TD
    A[Factory Inspection & Testing] --> B[Hydraulic Test @ 2× Working Pressure]
    B --> C[Certification Mark Check]
    C --> D[Delivery to Site]
    D --> E[On-site Inspection & Sounding]
    E -->|Defective| F[Reject & Remove]
    E -->|Accepted| G[Proceed to Installation]

Summary: IS 2065 mandates strict factory testing, certification, and on-site inspection with hydraulic pressure tests and chlorine disinfection protocols for water supply pipes and fittings.

IS 2065 Key Guidelines for Maintenance & Cleaning of Storage Tanks

1. Inspection & Cleaning (Clause 15.1)

• Regular inspection for corrosion and water tightness.
• If corrosion is detected:
  • Empty tank.
  • Wire-brush to remove loose material (do not scrap).
  • Clean and coat with inert anti-corrosive paint (no taste/odor contamination).
• Plug outlet before cleaning to prevent debris entry.
• Examine tank post-cleaning for corrosion and leaks.

2. Disinfection Procedure (Clause 13.2)

• Fill tank and pipes with water; flush thoroughly.
• Refill tank; add chlorine disinfectant gradually for thorough mixing.
• Chlorine dose: 50 ppm (parts per million).
• If bleaching powder used:
  • 150 g powder per 1000 L water (mixed to creamy consistency before adding).
• After filling, stop supply; open taps progressively until chlorine smell detected.
• Top up tank with water + disinfectant; keep charged for ≥ 3 hours.
• Flush tank and pipes thoroughly before domestic use.

3. Underground Tank Specifications (Clause 11.9)

• Tank top ≥ 30 cm above highest flood level or manhole cover raised accordingly.
• Design for complete drainage; no water pooling around tank.
• Watertight with smooth inner surfaces.
• Level top to avoid water accumulation.
• Concrete cover with mosquito-proof, leakproof manhole covers.
• Proper sealing around suction pipes; spill water discharge provisions.

4. Materials & Construction (Clause 11.2)

• Tanks made from iron, wrought iron, mild steel plates/sheets; watertight without putty.
• Adequate strength and thickness.
• RCC or other suitable materials allowed.

Summary Table: Chlorine Disinfection Dosage

flowchart TD
    A[Start Cleaning] --> B[Plug Outlet]
    B --> C[Empty Tank]