Wooden sofa-cum-bed

IS 12680 Scope Summary

• Scope: IS 12680 covers specifications for steel tubes and tubulars for structural purposes.
• Clause 3.0 defines key terms used in the standard.
• Clause 8.1 outlines general requirements for materials, workmanship, and testing.
• Clause 2.1 references related Indian Standards (Annex A) for complementary guidelines.
• Clause 4.9 specifies surface finishes like enamel, polish, and varnish as per IS 2338 (Part 2):1967.
• Clause 5 details dimensions and tolerances for steel tubes, ensuring uniformity and fit.

Key Points on Dimensions & Tolerances (Clause 5)

Related IS Codes (Annex A)

• IS 1239 – Mild steel tubes
• IS 3589 – Steel tubes for structural purposes
• IS 2338 – Surface finishes (enamel, polish, varnish)

flowchart LR
A[IS 12680 Scope] --> B[Definitions (Clause 3.0)]
A --> C[General Requirements (Clause 8.1)]
A --> D[Dimensions & Tolerances (Clause 5)]
A --> E[Surface Finish per IS 2338 (Clause 4.9)]
A --> F[Related IS Codes (Annex A)]

For detailed design, always refer to the specific clauses and tables within IS 12680 and its adjunct standards.

Referenced Indian Standards in IS 12680:1989 (Annex A)

IS 12680 refers to several Indian Standards essential for wooden furniture (sofa-cum-bed) design, manufacture, and finishing:

Key Points:

• These standards cover material quality, preservation, adhesives, fasteners, finishing, and testing.
• Always use the latest editions and amendments.
• Refer to IS 2:1960 for rounding off numerical values in test results.

Summary Table for Quick Reference

IS 12680 - Definitions & Key References

• Clause 3.0 defines terms specific to this standard for clarity and uniformity.
• Clause 2.1 lists essential Indian Standards (Annex A) related to timber, plywood, wood finishes, adhesives, and fasteners, which complement IS 12680.

Key Referenced IS Codes (Annex A):

Notes:

• Definitions ensure consistent interpretation of terms like timber, plywood, particle boards, adhesives, and finishes.
• Refer to these IS codes for detailed specifications, test methods, and quality criteria.
• Moisture content, preservation, and finishing standards are critical for structural performance and durability.

flowchart LR
    A[IS 12680 Definitions] --> B[Timber Properties]
    A --> C[Plywood & Boards]
    A --> D[Adhesives & Finishes]
    B --> IS287[Moisture Content (IS 287)]
    C --> IS303[Plywood (IS 303)]
    D --> IS2338[Finishing (IS 2338)]

For detailed formulas or tables, consult the respective IS codes listed in Annex A.

IS 12680 - Materials: Key Specifications & References

• Enamel, Polish, Varnish: Must comply with IS 2338 (Part 2): 1967 — Code of practice for finishing of wood and wood-based materials.

• Moisture Content for Timber: Refer IS 287:1973 for max permissible moisture content depending on timber use.

• Preservation of Timber: Follow IS 401:1982 for preservation methods.

• Seasoning of Timber: As per IS 1141:1973.

• Particle Boards & Block Boards:

  • Particle boards: IS 3087:1986
  • Veneered particle boards: IS 3097:1980
  • Block boards: IS 1659:1979

• Adhesives: Polyvinyl acetate dispersions per IS 4835:1979.

• Screws: Slotted countersunk wood screws as per IS 1365:1978 and IS 6760:1972.

Moisture Content Guideline (from IS 287:1973)

Additional Notes

• For ECO Mark medium density fibreboard, refer IS 12486:1988.

• All finishes must be tested for resistance to dry/wet heat, marking by oils/fats/liquids as per IS 5807 Part 1 & 2.

flowchart LR
    Materials --> Finishing[IS 2338 (Part 2): 1967]
    Materials --> Moisture[IS 287:1973]
    Materials --> Preservation[IS 401:1982]
    Materials --> Seasoning[IS 1141:1973]
    Materials --> Boards[IS 3087, 3097, 1659]
    Materials --> Adhesives[IS 4835:1979]
    Materials --> Screws[IS 1365, 6760]

This summary ensures compliance with IS 12680

IS 12680: Dimensions and Tolerances for Sofa-Cum-Bed (Clause 5.1)

• Seat height: 380 to 400 mm
• Clear seat depth: 550 to 600 mm
• Height of back above seat: 400 to 450 mm

Tolerance: ± 5 mm on all the above dimensions.

Summary Table

Additional References:

• Enamel, polish, varnish per IS 2338 (Part 2): 1967
• Screws per IS 1365: 1978 or IS 6760: 1972
• Annex A lists related Indian Standards for adjunct specifications.

graph LR
A[Seat Height: 380-400 mm] --> B[Clear Seat Depth: 550-600 mm]
B --> C[Back Height above Seat: 400-450 mm]

This ensures ergonomic comfort and manufacturing consistency for sofa-cum-beds.

Key Specifications & References for Construction and Joinery (IS 12680)

• Timber Moisture Content: As per IS 287:1973, maximum permissible moisture content varies by timber use. Proper seasoning per IS 1141:1973 is mandatory.
• Preservation: Sapwood of durable species and non-durable timbers must be treated as per IS 401:1982.
• Wood Types for Frames: Use timbers classified in IS 13622:1993 for furniture.
• Panels: Use wood particle board, veneered particle board, plywood, or block board with 20 mm ±1 mm thickness.
• Joinery: Follow IS 3845:1965 for joints in wooden furniture.
• Fasteners: Use slotted countersunk screws as per IS 1365:1978 and IS 6760:1972.
• Finishing: Refer to IS 2338 (Part 2):1967 and IS 5807 (Part 1):1975 for finishing and durability tests.

Typical Joinery Angle for Sofa-cum-bed (Fig.1)

• Included angle between seat and back: 110° to 115°
• Seat height (A) and back height (C) as per ergonomic standards.

graph LR
A[Seat Height] -->|Supports| B[Back Surface]
B -->|Forms angle 110°-115°| C[Back Angle]

Summary: Use well-seasoned, preserved timber with controlled moisture content; 20 mm thick boards; joints per IS 3845; and standard screws for durable, quality joinery.

IS 12680: Performance Requirements of Finish

Key performance tests for finishes (enamel, polish, varnish) are referenced to IS 5807 and IS 2338 (Part 2):

1. Resistance to Dry Heat (Clause 7.2)

• Tested as per IS 5807 (Part 1): 1975.
• Minimum qualifying average rating: 7 (scale defined in IS 5807 Part 1).

2. Resistance to Marking by Oils and Fats (Clause 7.4)

• Tested as per IS 5807 (Part 3): 1971.
• Test results must conform to criteria 5 and 6 of IS 5807 (Part 3).

3. Resistance to Marking by Liquids (Clause 7.5)

• Tested as per IS 5807 (Part 4): 1975.
• Minimum qualifying average rating: 8 (per IS 5807 Part 4).

4. Enamel, Polish, and Varnish Standards

• Must comply with IS 2338 (Part 2): 1967 for schedules and specifications.

Summary Table

This ensures the finish durability and suitability for intended applications under thermal and chemical exposures.

IS 12680: Marking and Identification - Key Points

1. Resistance to Marking by Liquids (Clause 7.5)

• Test as per IS 5807 (Part 4): 1975.
• Minimum qualifying average rating must comply with Clause 8 of IS 5807 (Part 4).
• Ensures surface durability against liquid marks.

2. Resistance to Marking by Oils and Fats (Clause 7.4)

• Test as per IS 5807 (Part 3): 1971.
• Must meet requirements in Clauses 5 and 6 of IS 5807 (Part 3).

3. Finishing Standards (Clause 4.9)

• Enamel, polish, and varnish must follow schedules in IS 2338 (Part 2): 1967.

4. Related Standards for Marking & Identification

Summary Table: Resistance Tests

flowchart TD
    A[Surface Sample] --> B{Test for Marking Resistance}
    B -->|Liquids| C[IS 5807 Part 4:1975]
    B -->|Oils & Fats| D[IS 5807 Part 3:1971]
    C --> E{Meets Clause 8?}
    D

IS 12680: Additional Requirements for ECO Mark

The ECO Mark certification requires products to meet stricter environmental and quality standards as per associated IS codes:

Key Specifications for ECO Mark

• Particle Board:
  Must conform to IS 3087:1985 requirements for ECO Mark.
  (Clause 4.2)

• Medium Density Fibreboard (MDF):
  Must meet IS 12486:1988 standards for ECO Mark.
  (Clause 4.6)

• Plywood:
  Must comply with IS 303:1989 for ECO Mark.
  (Clause 4.5.1)

Manufacturer's Responsibility

• Provide documentary evidence (certification/declaration) to BIS when applying for ECO Mark.
  (Clause 8.2)

Summary Table

This ensures the product meets environmental safety and quality benchmarks for ECO Mark certification under IS 12680.

IS 12680 Referenced Indian Standards (Annex A Highlights):

Key Notes:

• These standards cover timber moisture content, preservation, seasoning, plywood, particle boards, adhesives, finishes, and fasteners.
• Refer to each IS for detailed specifications, test methods, and quality control.
• IS 2:1960 governs rounding off numerical values in test results.
• BIS periodically revises these standards; always check for latest amendments.

Example: Moisture Content Limits (IS 287:1973)

flowchart LR
    A[IS 12680] --> B[Timber Moisture Content (IS 287)]
    A --> C[Plywood (IS 303)]
    A --> D[Particle Boards (IS 3087, IS 3097)]
    A --> E[Timber Preservation (IS 401)]
    A --> F[Fasteners (IS 1365)]