Methods of building and civil engineering works, Part 28: Sound insulation works
1992 Edition

IS 1200 Part 28: Scope Overview and Specifications

• Coverage: Defines measurement methods for civil engineering projects, excluding river valley schemes (see CED 44).
• Measurement Rules:
  • Final values to be rounded according to IS 2:1960, maintaining the original significant digits.
  • Curved, conical, and spherical elements require separate description with radius details (Clause 7.2).
  • Sound insulation works above 10 meters are measured in 5-meter increments if no intermediate floors exist; otherwise, measured per floor (Clause 7.4).

Rounding Procedures (per IS 2:1960)

• Preserve the same number of significant figures as specified.
• Round the last digit up if the succeeding digit is 5 or greater.

Measurement Summary Table (Clause 7.4)

Visual Diagram (Measurement Scope)

flowchart TD
    A[Civil Engineering Projects] --> B[Exclude River Valley Projects]
    B --> C[Measurement as per IS 1200 Part 28]
    C --> D[Curved/Conical/Spherical Elements]
    C --> E[Sound Insulation Work]
    E --> F{Height Above 10 m?}
    F -- Yes --> G[Measure in 5 m Segments]
    F -- No --> H[Measure by Storey]

Note: Always consult the latest BIS edition and amendments.

IS 1200 Part 28: Core Principles for Measuring Sound Insulation

Highlights:

• Scope: Measurement applies to soundproofing in building and civil engineering structures (Clause 1.1).

• Isolated Widths: Sound insulation in narrow bands such as corners, window sills, door/window jambs, recessed panels, and rounded angles must be measured distinctly (Clause 5.8).

• Rounding Off:

  • Apply IS 2:1960 rounding rules for final values.
  • Maintain identical significant figures as specified in the standard (Clause 6).

• Curved Surfaces: Curved, conical, and spherical surfaces require separate descriptions including radius details (Clause 7.2).

Summary Table:

Rounding Details (IS 2:1960):

• Drop digit >5 rounds up.
• Drop digit <5 rounds down.
• Drop digit =5 rounds to nearest even number.

flowchart LR
    A[Initiate Measurement] --> B{Isolated Width?}
    B -- Yes --> C[Measure Separately]
    B -- No --> D[Proceed with Standard Measurement]
    D --> E{Curved Surface?}
    C --> E
    E -- Yes --> F[Describe with Radius]
    E -- No --> G[Record Measurement]
    F --> G
    G --> H[Apply IS 2:1960 Rounding]
    H --> I[Finalize Value]

This approach guarantees consistent and precise measurement of sound insulation as per IS 1200 Part 28.

IS 1200 Part 28: Guidelines for Bills of Quantities (BoQ)

• Item Grouping (Clause 2.1): BoQ items may be consolidated where appropriate to simplify documentation.

• Specification Details (Clause 4.1): Each sound insulation category should be measured distinctly with information on:

  • Material specifications
  • Number and thickness of coats
  • Surface finish
  • Base type
  • Special shapes such as curved, conical, elliptical forms with radius values

• Measurement Relevance: Accurate measurement is crucial from project inception to final payment. IS 1200 encourages standardized measurement to prevent discrepancies.

Typical BoQ Format (Summary)

General Measurement Formula

[ \text{Quantity} = \text{Length} \times \text{Width} \times \text{Thickness} ]

For curved or special geometries, apply the specified radius or geometric formulas.

flowchart TD
    A[Define Project Scope] --> B[Identify BoQ Items]
    B --> C{Combine Items?}
    C -->|Yes| D[Group Items]
    C -->|No| E[Keep Items Separate]
    D --> F[Specify Material and Coating Details]
    E --> F
    F --> G[Measure Quantities]
    G --> H[Compile BoQ]
    H --> I[Use for Tender and Payment]

Summary: IS 1200 Part 28 provides a systematic approach for measurement and item description to promote clarity and consistency in BoQ preparation.

IS 1200 Part 28: Essential Aspects of Sound Insulation Work

1. Work Description (Clause 3.1)

• Material types and workmanship must be fully detailed.
• Work execution should be accurately represented.

2. Soundproofing Parameters (Clause 4.1)

Details to specify for each insulation task:

3. Measurement (Clause 5)

• Each insulation type is measured individually.
• Measurements include thickness and surface area.

Engineering Insight:

• Sound Transmission Loss (STL) depends on density, thickness, and frequency.
• Mass Law formula:

[ STL = 20 \log (m \times f) - 47 ]

where:

• ( STL ) = sound transmission loss in decibels
• ( m ) = mass per unit area (kg/m²)
• ( f ) = frequency in Hz

flowchart TD
    A[Define Insulation Work] --> B[Specify Material]
    B --> C[Detail Number & Thickness of Coats]
    C --> D[Specify Surface Finish]
    D --> E[Identify Base Material]
    E --> F[Describe Special Shapes & Radii]
    F --> G[Measure Each Classification]
    G --> H[Perform Execution and Quality Assurance]

Summary: IS 1200 Part 28 stresses detailed documentation of materials, layering, finishes, bases, and form for sound insulation, with distinct measurement for each category.

IS 1200 Part 28: Measurement Methodology - Main Points

• Units of Measurement:

  • Linear measurements recorded up to 0.01 m for lengths ≤ 25 m.
  • For lengths exceeding 25 m, measurements are rounded to the nearest 0.1 m.
  • Areas calculated to the nearest 0.01 m².

• Measurement Principles:

  • Quantities represent net work done, excluding overlaps.
  • Measurements taken as fixed in position on site.
  • Sound insulation on ceilings, walls, floors measured separately.

• Objectives:

  • Standardize measurement techniques across organizations.
  • Eliminate ambiguity in quantity estimations.
  • Support clear financial and technical evaluation.

Common Measurement Formulae

Simplified Measurement Flow

flowchart TD
    A[Start Measurement] --> B[Identify Item]
    B --> C[Measure Dimensions (0.01/0.1 m accuracy)]
    C --> D[Compute Area/Volume]
    D --> E[Record Net Quantity]
    E --> F[Separate Special Works (Sound Insulation)]
    F --> G[Complete Measurement]

Note: Consult IS 1200 Part 28 for exact clauses on specific measurement details.

IS 1200 Part 28: General Measurement Rules for Soundproofing Work

Key Points:

• Rounding Rules:

  • Follow IS 2:1960 for rounding numerical values.
  • Maintain the number of significant digits as stated in the standard.

• Measurement Details (Clause 5.8):

  • Measure sound insulation in isolated widths separately, including:
    • Bands
    • Corners
    • Window sills
    • Door/window jambs
    • Recessed panels
    • Rounded angles

• Scope (Clause 1.1):

  • Applies to soundproofing in buildings and civil engineering structures.

Measurement Guidelines:

• Precisely measure length, width, and thickness of insulation materials.
• Isolated or irregular sections should be measured individually to prevent inaccuracies.
• Consistent use of metric units (meters, square meters) is required.

Summary Table for Sound Insulation Components

flowchart LR
    A[Initiate Measurement] --> B{Component Type?}
    B -->|Flat Surface| C[Measure Length & Width]
    B -->|Isolated Width| D[Measure Linear Width Separately]
    B -->|Rounded Angle| E[Measure Curved Surface Area]
    C --> F[Calculate Area (m²)]
    D --> F
    E --> F
    F --> G[Apply IS 2:1960 Rounding]
    G --> H[Record Final Measurement]

**Use IS 1200 Part 28 alongside IS 2:1960 for consistent and precise measurement and rounding standards.

IS 1200 Part 28: Detailed Measurement Procedures - Highlights

• Measurement Precision:

  • Linear measurements to an accuracy of 0.01 m.
  • Lengths over 25 m measured with 0.1 m precision.
  • Area measurements to 0.01 m² precision.

• Measurement Standards:

  • Only net quantities fixed in place are recorded.
  • Uniform decimal notation ensures clarity.
  • Specialized works such as sound insulation on ceilings, walls, and floors are measured separately.

• Purpose:

  • Standardizes measurement techniques.
  • Facilitates clear communication and reduces disputes.
  • Enables accurate cost estimation and project tracking.

Accuracy Summary

flowchart TD
    A[Begin Measurement] --> B{Length ≤ 25 m?}
    B -- Yes --> C[Measure to 0.01 m]
    B -- No --> D[Measure to 0.1 m]
    C & D --> E{Calculate Area?}
    E -- Yes --> F[Compute to 0.01 m²]
    E -- No --> G[Record Linear Value]
    F & G --> H[Net Quantity Fixed in Position]
    H --> I[Use for Costing & Billing]

Refer to relevant IS 1200 parts for item-specific measurement details.