Wooden sofa-cum-bed
1989 Edition

Overview of Scope for Wooden Sofa-Cum-Beds

• Defines the applicable range for wooden sofa-cum-beds used as domestic furniture.
• Clarifies terminology used within the standard.
• Details general requirements related to materials, workmanship, and testing procedures.
• Lists related Indian Standards that complement this code.
• Specifies surface finishing requirements including enamel, polish, and varnish.
• Sets dimensional and tolerance guidelines to ensure consistency.

Highlights on Dimensions and Tolerances

Associated Indian Standards

• IS 1239 – Mild steel tubes
• IS 3589 – Structural steel tubes
• IS 2338 – Surface finish codes

flowchart LR
A[Scope & Definitions] --> B[General Requirements]
A --> C[Material Dimensions & Tolerances]
A --> D[Surface Finishes as per IS 2338]
A --> E[Referenced Indian Standards]

For specific construction details, refer to individual clauses within the standard.

Indian Standards Referenced by This Code

IS 12680 cites various Indian Standards pivotal for design, manufacturing, and finishing of wooden sofa-cum-beds:

Important Notes

• These standards address material quality, preservation, adhesives, fasteners, finishing, and testing.
• Always consult the most current versions and amendments.
• IS 2:1960 governs rounding off numerical test results.

Quick Reference Table

Key Definitions and References in IS 12680

• Clause 3.0 provides precise definitions of terms used within the document for clarity and consistency.
• Clause 2.1 enumerates Indian Standards that support the understanding of materials, adhesives, finishes, and fasteners relevant to wooden furniture.

Principal Supporting IS Codes

Notes

• Definitions cover essential concepts like types of timber, adhesives, and surface finishes.
• These referenced standards provide detailed specifications and test methods.
• Moisture content and preservation are critical for structural integrity and durability.

flowchart LR
A[Standard Definitions] --> B[Timber Properties]
A --> C[Boards & Panels]
A --> D[Adhesives & Finishing]
B --> IS287(Moisture Content)
C --> IS303(Plywood)
D --> IS2338(Finishing)

For complete technical details, consult the respective Indian Standards listed.

Materials Requirements as per IS 12680

• Surface Finishes: Enamel, polish, and varnish must comply with IS 2338 (Part 2):1967.
• Timber Moisture: Maximum moisture content should follow IS 287:1973, varying by timber application.
• Timber Treatment: Preservation of sapwood and non-durable timbers is to be done as per IS 401:1982.
• Seasoning: Timber seasoning must be in accordance with IS 1141:1973.
• Wood-Based Panels: Particle boards (IS 3087:1986), veneered particle boards (IS 3097:1980), and block boards (IS 1659:1979) are specified for use.
• Adhesives: Polyvinyl acetate adhesives should meet IS 4835:1979.
• Fasteners: Slotted countersunk wood screws must comply with IS 1365:1978 and IS 6760:1972.

Moisture Content Limits (IS 287:1973)

Notes

• ECO Mark medium density fibreboard requirements are covered under IS 12486:1988.
• Finishes must pass resistance tests against dry heat, wet heat, oils, fats, and liquids as per IS 5807 Parts 1 and 2.

flowchart LR
Materials --> Finishes[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 materials conform to IS 12680 requirements.

IS 12680: Standard Dimensions and Permissible Tolerances for Sofa-Cum-Beds

• Seat Height: 380 to 400 mm
• Seat Depth (Clear): 550 to 600 mm
• Back Height Above Seat: 400 to 450 mm

Tolerance: ±5 mm for all the above measurements.

Dimension Summary Table

Additional Details:

• Surface finishes governed by IS 2338 (Part 2): 1967
• Screws must meet IS 1365:1978 or IS 6760:1972
• Related Indian Standards are listed in Annex A

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

These dimensions support ergonomic comfort and ensure consistent product quality.

Construction and Jointing Requirements in IS 12680

• Timber Moisture & Seasoning: Timber must adhere to moisture limits set in IS 287:1973 and be properly seasoned as per IS 1141:1973.
• Preservation: Sapwood of durable species and all timber from non-durable species require treatment following IS 401:1982.
• Approved Timber Types: Use furniture-grade timber per IS 13622:1993.
• Panels: Employ particle board, veneered particle board, plywood, or block board of 20 mm ±1 mm thickness.
• Joinery: Must conform to IS 3845:1965 standards for wooden furniture joints.
• Fasteners: Use slotted countersunk screws according to IS 1365:1978 and IS 6760:1972.
• Finishing: Finish coatings must comply with IS 2338 (Part 2):1967 and durability tests per IS 5807 (Part 1):1975.

Typical Joinery Angles

• Seat to Backrest Angle: Between 110° and 115°

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

Summary: Utilize well-seasoned and preserved timber, 20 mm thick panels, compliant joints, and standard screws to ensure durability and quality assembly.

Performance Criteria for Surface Finishes in IS 12680

Finishes including enamel, polish, and varnish must meet the following test requirements referencing IS 5807 and IS 2338 (Part 2):

1. Resistance to Dry Heat

• Conducted as per IS 5807 (Part 1): 1975
• Minimum average rating required: 7

2. Resistance to Marking by Oils and Fats

• Conducted per IS 5807 (Part 3): 1971
• Must satisfy criteria 5 and 6

3. Resistance to Marking by Liquids

• Tested according to IS 5807 (Part 4): 1975
• Minimum average rating required: 8

4. Compliance with Enamel, Polish, and Varnish Standards

• Must conform to IS 2338 (Part 2): 1967

Summary Table

This ensures the applied finishes maintain durability against thermal and chemical exposures.

Marking and Identification Requirements per IS 12680

Liquid Mark Resistance

• Tested according to IS 5807 (Part 4): 1975
• Must meet minimum average rating as described in Clause 8

Oils and Fats Mark Resistance

• Tested as per IS 5807 (Part 3): 1971
• Compliance with Clauses 5 and 6 is mandatory

Finishing Requirements

• Enamel, polish, and varnish must adhere to IS 2338 (Part 2): 1967 finishing schedules

Relevant Standards for Marking & Identification

Test Summary Table

flowchart TD
    A[Surface Sample] --> B{Marking Resistance Test}
    B -->|Liquids| C[IS 5807 Part 4]
    B -->|Oils & Fats| D[IS 5807 Part 3]
    C --> E{Meets Clause 8?}
    D --> F{Meets Clauses 5 & 6?}

This ensures surface durability and consistent product identification.

ECO Mark Certification Requirements in IS 12680

To qualify for ECO Mark certification, wooden sofa-cum-beds must satisfy enhanced environmental and quality standards:

Material Standards for ECO Mark

• Particle Board: Must comply with IS 3087:1985 ECO Mark requirements (Clause 4.2).
• Medium Density Fibreboard (MDF): Must meet IS 12486:1988 standards for ECO Mark (Clause 4.6).
• Plywood: Required to conform to IS 303:1989 ECO Mark criteria (Clause 4.5.1).

Manufacturer Obligations

• Submit valid certification or declaration documents to BIS during ECO Mark application (Clause 8.2).

Summary Table

This ensures products meet stringent environmental safety and quality standards necessary for ECO Mark accreditation.

Referenced Indian Standards in IS 12680 (Annex A):

Notes:

• These cover timber moisture, preservation, seasoning, plywood, particle boards, adhesives, finishes, and fasteners.
• Each standard should be referenced for detailed technical specifications.
• Numerical rounding is governed by IS 2:1960.
• Users should verify the latest versions and amendments.

Example Moisture Content Limits (IS 287:1973)

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