Code of Practice for Construction of Floor and Roof with Joists and Filler Blocks, Part 1: With Hollow Concrete Filler Blocks

IS 6061 (Part 1) - 1971: Introduction & Key Specifications

• Scope: Code of practice for floors/roofs with precast reinforced concrete joists and hollow cement concrete filler blocks.
• Advantages: Durability, fire resistance, thermal insulation, reduced dead load, speed of construction, no shuttering needed.
• Limitations: Not suitable for floors subjected to impact or vibration.
• Testing:
  • At least 2 blocks/day or 2 per 1000 blocks tested for dimensions & breaking strength (Clause 2.1.2).
  • Breaking strength test values as per Table B-2 (dimensions in mm).
• Floor Finishes (Clause 7.1.1):

  Type	IS No.
  Cement concrete tiles	IS 1443-1959
  Terrazzo	IS 2114-1962
  Rubber	IS 1197-1970
  Linoleum	IS 1198-1958
  PVC	IS 5318-1969
  Epoxy resin	IS 4631-1968
  Bitumen mastic	IS 1196-1968

Note: Final test values should be rounded per IS 2-1960.

flowchart LR
    A[Precast Reinforced Concrete Joists] --> B[Hollow Cement Concrete Filler Blocks]
    B --> C[Floor/Roof Construction]
    C --> D[Advantages: Durability, Fire Resistance, Thermal Insulation]
    C --> E[Limitations: No Impact/Vibration Loads]
    C --> F[Testing: Dimensional & Breaking Strength]

For detailed dimensions and breaking strength values, refer to Table B-2 in Clause 2.1.2 of IS 6061 (Part 1).

IS 6061 Part 1 - Scope: Key Specifications & Tables

Scope Summary:

• Covers hollow cement concrete filler blocks used in construction.
• Specifies testing requirements, dimensional tolerances, and breaking strength tests.

Key Specifications:

• Sampling for Testing (Clause 2.1.2):

  • At least two blocks per day or two blocks per 1000 blocks, whichever is less, must be tested.

• Dimensional Tolerances (Clause 1.2):

  • Height & Breadth: ±1.5 mm
  • Length: +3.0 mm

Breaking Strength Test (Table B-2):

Typical Hollow Concrete Filler Block (Fig. 2):

• Standard shapes and sizes are defined (refer IS 6061 Fig. 2).
• Blocks must meet dimensional tolerances and strength criteria.

Related IS Codes for Floor Finishes (Clause 7.1.1):

Summary Diagram:

flowchart TD
    A[Hollow Cement Concrete Blocks] --> B[Sampling for Test]
    B --> C{2 blocks/day or 2 per 1000}
    A --> D[Dimensional Tolerances]
    D --> E[Height & Breadth ±1.5 mm]
    D --> F[Length +3.0 mm]
    A --> G[Breaking Strength Test]
    G --> H[Minimum 2 blocks tested]

For detailed dimensions and test procedures, consult **IS 6061 (Part

IS 6061 Part 1 – Design Considerations for Precast RCC/PSC Joists with Hollow Concrete Filler Blocks

Key Design Points (Clause 2 & 3)

• System: Precast RCC/prestressed concrete joists + hollow cement concrete filler blocks + in-situ RCC decking.
• Joist Spacing: As per design, spanning between supports (walls/beams) (Clause 6.1).
• Joist Detailing: Follow Appendix A for reinforcement and prestressing details (Clause 3.5).

Hollow Concrete Filler Blocks (Clause 2.1.2)

• Testing: Minimum 2 blocks/day or 2 per 1000 blocks tested for dimensions & breaking strength.
• Dimensions: As per Fig. 2 typical block (dimensions in mm).
• Breaking Strength: Refer Table B-2 for minimum breaking strength values (not fully provided here).

General Specifications

• Use coarse and fine aggregates as per relevant IS standards.
• Follow IS 456 for plain and reinforced concrete design.
• Proper stacking and storage recommended for materials.

Typical Breaking Strength Test Table (Example Format):

(Refer actual IS 6061 Table B-2 for exact values)

flowchart LR
    A[Precast RCC/PSC Joists] --> B[Placed at Designed Spacing]
    B --> C[Span Between Supports]
    C --> D[Hollow Concrete Filler Blocks]
    D --> E[In-situ RCC Decking]

Summary: Design precast joists per Appendix A, place at specified spacing, use tested hollow blocks, and cast in-situ RCC decking on top. Follow IS 456 and aggregate specs for durability and strength.

IS 6061 Part 1 (1971) — Key Specifications for Materials

1. Concrete Blocks (Clause 2.1.2)

• Sampling: At least 2 blocks per lot/day or 2 per 1000 blocks (whichever less) tested.
• Tests: Dimensions and breaking strength.
• Units: All dimensions in millimeters.

2. Concrete Grade for Precast Joists (Clause 2.1)

• Concrete grade: M-200 as per IS 456:1964.

3. Floor Finishes (Clause 7.1.1)

*Codes of practice for laying and finishing are referenced.

Summary of Material Testing for Hollow Concrete Blocks

For reinforcement details, refer to IS 6061 Part II or IS 456 for concrete and reinforcement specifications.

flowchart TD
    A[Concrete Blocks] --> B[Sampling: 2 blocks/day or 2/1000 blocks]
    B --> C[Tests: Dimensions & Breaking Strength]
    D[Precast Joists] --> E[Concrete Grade M-200 (IS 456)]
    F[Floor Finishes] --> G[Cement Concrete Tiles (IS 1443)]
    F --> H[Terrazzo (IS 2114)]
    F --> I[Rubber (IS 1197)]
    F --> J[Linoleum (IS 1198)]
    F --> K[PVC (IS 5318)]
    F --> L[

IS 6061 Part 1 - Programming the Work: Key Points

1. Preparation of Supporting Elements (Clause 4.1):

   • Complete and cure walls, pillars, beams, and frames before flooring/roofing.
   • Provide a 75 mm thick plain concrete bed (1:2:4 mix) over load-bearing walls if needed.
   • Ensure top surfaces are level-finished.
   • Arrange for fixing service pipes, conduits, fixtures passing through the floor.

2. Concrete Grade for Joists (Clause 2.1):

   • Use M-200 grade concrete as per IS 456-1964.

3. Precast Hollow Cement Concrete Filler Blocks (Clause 3.6 & Appendix B):

   • Blocks must conform to specified dimensions and breaking strength.
   • Testing: At least 2 blocks per day or per 1000 blocks tested for strength and dimensions.

Typical Plain Concrete Bed Specification:

Work Programming Flow (Simplified):

flowchart TD
    A[Complete Structural Elements] --> B[Cure Elements Properly]
    B --> C[Provide Concrete Bed if Needed]
    C --> D[Level Finish Top Surface]
    D --> E[Arrange Service Fixings]
    E --> F[Start Flooring/Roofing Work]

Summary: Early completion and curing of supporting structures, proper leveling with a concrete bed, and coordination for services are essential before flooring/roofing. Use M-200 concrete for joists and ensure filler blocks meet IS 6061 specs.

IS 6061 Part 1: Storage, Transport & Handling of Materials

Key Specifications:

• Supporting Elements: Complete and cure walls, pillars, beams before flooring/roofing. Provide a 75 mm thick plain concrete bed (1:2:4 mix) over load-bearing walls if needed. Ensure level-finished top surfaces (Clause 4.1).

• Precast Joists Handling (Clause 6.1):

  • Lift joists carefully from platform.
  • Provide temporary supports at designer-indicated points during stacking and transport.
  • Stack on firm, even ground/platform.
  • If stacked in multiple rows, props must align vertically.

• Storage of Materials (Clause 5.1):

  • Follow IS 4082-1967 recommendations for cement, aggregates, and other materials.
  • Observe precautions to avoid damage during storage, transport, and handling of precast elements.

Table: Breaking Strength Test on Hollow Concrete Filler Blocks (Clause 2.1.2)

Summary Diagram of Handling Process

flowchart TD
    A[Material Arrival] --> B[Storage on firm ground]
    B --> C[Temporary supports at design points]
    C --> D[Lifting with care]
    D --> E[Transport with supports]
    E --> F[Placement without damage]

References:

• IS 6061 (Part 1) - 1971
• IS 4082-1967 (Storage of Cement & Aggregates)

Ensure all handling and storage follow these guidelines to maintain structural integrity and material quality.

IS 6061 Part 1: Laying Floor or Roof with Joists and Hollow Blocks

Key Components (Clause 2.1.1)

• Precast reinforced/prestressed concrete joists spaced suitably.
• Precast cement concrete hollow filler blocks between joists.
• Nominally reinforced structural topping concrete cast in situ.
• Floor/roof finish (e.g., tiles, terrazzo).
• Optional ceiling finish below joists and blocks.

Important Specifications:

• Storage & Handling: Follow IS 4082-1967 for materials storage.
• Joist Spacing: As per design loads and span, typically 450-600 mm center-to-center.
• Topping Thickness: Usually 40-50 mm nominal thickness with reinforcement mesh.

Floor Finishes (Clause 7.1.1, Table)

Typical Floor Section (Mermaid Diagram)

graph TD
    A[Ceiling Finish (optional)] --> B[Precast Hollow Blocks]
    B --> C[Precast Concrete Joists]
    C --> D[Structural Topping Concrete]
    D --> E[Floor Finish]

Summary:

• Use precast joists + hollow blocks + topping for lightweight, economical floors.
• Follow IS codes for material handling, joist spacing, topping, and finishes.
• Choose floor finish per IS 6061 Part 1 Table 7.1.1 for durability and aesthetics.

IS 6061 Part 1 (1971) – Floor Finishes Summary

Key Standards for Floor Finishes (Clause 7.1.1)

Concrete Topping and Preparation (Clause 7.1 & 4.1)

• Concrete topping per IS 456 grade M-200 (1:1.5:3 approx.) is laid before finishes.
• Supporting elements (walls, beams) must be level-finished and well-cured.
• A 75 mm thick plain concrete bed (1:2:4 mix) may be provided over load-bearing walls.
• Provision for service pipes/conduits must be planned before flooring.

Typical Concrete Mix for Flooring Bed

Diagram: Floor Finish Layers

graph TD
    A[Supporting Structure] --> B[Concrete Bed (75 mm, 1:2:4)]
    B --> C[Concrete Topping (M-200 Grade)]
    C --> D[Floor Finish (per IS codes)]
    D --> E[Final Floor Surface]

Recommendations

• Follow specific IS codes for each finish type for detailed laying procedures.
• Ensure curing of concrete bed and topping before applying finishes.
• Plan for waterproofing as per IS 1346, 3036, or 4365 if

Key Specifications & Design Guidelines for Precast Reinforced/Prestressed Concrete Joists (IS 6061 Part 1):

• Span Limits:

  • Maximum span: 6 m (Clause 2.2.2)
  • Depth:
    • Up to 4.2 m span: 150 mm
    • 4.2 m to 6 m span: 200 mm (Clause A-1.1)

• Width: Uniform width throughout the joist (Clause A-1.1).

• Design Codes:

  • Reinforced concrete joists: Design as per IS 456:1964
  • Prestressed concrete joists: Design as per IS 1343:1960 (Clauses 2.2.3, A-3.1)

• Reinforcement:

  • Follow IS 456 for reinforced concrete joists.
  • Follow IS 1343 for prestressed joists (Clause A-3.1).

• Preparation: Details for fabrication are in Appendix A of IS 6061 Part 1 (Clause 3.5).

Typical Depth vs Span Recommendation

Design Principles Summary

• Use flexural design formulas from IS 456/IS 1343.
• Ensure adequate prestressing force or reinforcement area to resist bending moments.
• Check deflection and crack width limits as per respective codes.

flowchart LR
    A[Span ≤ 4.2 m] --> B[Depth = 150 mm]
    A2[Span 4.2 to 6 m] --> B2[Depth = 200 mm]
    C[Design] --> D{Type of Joist}
    D -->|Reinforced| E[IS 456:1964]
    D -->|Prestressed| F[IS 1343:1960]
    G[Reinforcement] --> E & F

For detailed reinforcement layouts and prestressing details, refer to Appendix A of IS 6061 Part 1.

IS 6061 Part 1: Precast Hollow Cement Concrete Filler Blocks

Key Specifications (Clause 3.6 & Appendix B)

• Blocks must conform to Appendix B requirements.
• Typical block for 600 mm joist centres shown in Fig. 2.
• For spans ≥ 750 mm between joists, blocks must be reinforced.

Dimensions & Typical Section (Fig. 2)

• Blocks designed for 600 mm joist spacing.
• Hollow cores reduce weight and improve thermal insulation.
• Typical block size approx. 230 mm width × 100 mm height × 450 mm length (verify exact from Fig. 2).

Breaking Strength Test (Clause B-2, Table B-2)

• Test at least 2 blocks per lot or 2 blocks per 1000 blocks.
• Minimum breaking strength typically ≥ 3.5 MPa (confirm from Table B-2).
• Dimensions must be within tolerance limits.

Reinforcement (Clause 1.5)

• For spans ≥ 750 mm, provide suitable reinforcement inside hollow cores.
• Reinforcement increases load capacity and reduces block cracking.

Summary Table: Testing & Reinforcement

flowchart LR
    A[Precast Hollow Block] --> B{Joist Spacing}
    B -->|< 750 mm| C[No Reinforcement]
    B -->|≥ 750 mm| D[Provide Reinforcement]
    A --> E[Breaking Strength Test]
    E --> F{Test 2 blocks per lot or 2/1000}
    F --> G[Pass if ≥ 3.5 MPa]

Note: Refer to Appendix B and Fig. 2 of IS 6061 Part 1 for exact dimensions and reinforcement details.