Code of practice for finishing of wood and wood-based materials, Part 1: Operations and workmanship

IS 2338 Part 1 - Scope & Key Specifications

• Scope: Covers finishes on wood and wood-based materials, focusing on efficient application and relevant information for quality results.

• Reference Standards:

  • Wood terms: IS 707-1958
  • Paints and allied materials: IS 1303-1963
  • Rounding off numerical values: IS 2-1960

• Necessary Information for Finishing (Clause 3.1):

  • Type and pretreatment of wood (preservation, seasoning)
  • Location and exposure conditions (weather)
  • Type of finish (pigmented, clear, etc.)
  • Previous finish info (for re-decoration)
  • Local atmospheric conditions (temperature, humidity, sunlight)

• Important Notes:

  • Finishes generally do not protect against biological decay but can prevent insect oviposition by continuous film.
  • Rounding off test values must follow IS 2-1960, matching significant figures of specified values.

No direct formulas or tables are provided in the scope; focus is on data requirements and references for terminology and procedures.

IS 2338 Part 1 - Definitions & Key References

• Clause 2.2: For wood and wood-based materials terminology, refer to IS 707-1958 (Glossary of timber, plywood, joinery terms).

• Clause 2.1: For paints and allied materials terminology, refer to IS 1303-1963 (Glossary of paint terms).

• Clause 3.1: Essential info for finishes on wood:

  • Type and pretreatment of wood (preservation, seasoning)
  • Location and exposure conditions (weather, sunlight)
  • Type of finish (pigmented, clear)
  • Previous finish info (for re-decoration)
  • Local atmospheric conditions (temperature, humidity)

No direct formulas or tables in definitions; key standards for terminology:

This ensures consistent understanding of terms in wood finishing and painting works.

flowchart LR
    A[Wood & Wood-based Materials Terms] -->|IS 707-1958| B[Definitions]
    C[Paints & Allied Materials Terms] -->|IS 1303-1963| B
    B --> D[Application of Finishes]
    D --> E[Wood Type & Pretreatment]
    D --> F[Exposure Conditions]
    D --> G[Finish Type]
    D --> H[Previous Finish]
    D --> I[Atmospheric Conditions]

IS 2338 (Part 1) - Key Points on Information and Instructions for Finishing Wood

Clause 3.1: Essential Information to be Furnished

• Wood type & pretreatment: Specify species, preservation, seasoning.
• Location: Exposure level to weather (indoor/outdoor).
• Finish type: Pigmented, clear, etc.
• Previous finish: Details for re-decoration.
• Atmospheric conditions: Temperature, humidity, sunlight exposure.

Clause 3.2: Limitations of Finishes

• Finishes do not protect wood from biological decay.
• Continuous finish films can prevent insect oviposition.

Clause 6.5: Application Guidelines

• Surfaces must be clean and dry.
• Apply finish by brush or spray under normal dry conditions.
• Application varies with paint type.

Rounding Off Values (IS 2-1960)

• Final values in tests must be rounded to the same number of significant figures as specified.

Summary Table: Information for Finishing Application

flowchart TD
    A[Start: Wood Finishing] --> B[Gather Wood Info]
    B --> C{Wood Type & Treatment?}
    C --> D[Specify Species, Seasoning]
    C --> E[Specify Preservation]
    B --> F[Location Exposure]
    B --> G[Finish Type]
    B --> H[Previous Finish Info]
    B --> I[Atmospheric Conditions]
    D & E & F & G & H & I --> J[Apply Finish (Brush/Spray)]
    J --> K[Ensure Clean & Dry Surface]
    K --> L[Finish Application Complete]

This ensures efficient, durable finishing aligned with IS 2338 Part 1 standards.

IS 2338 Part 1 - Design Considerations: Key Points

1. Timber Information (Clause 3.1)

For proper design and finishing, provide:

• Type of timber and pretreatment (preservation, seasoning)
• Location/exposure to weather
• Type of finish (pigmented, clear, etc.)
• Previous finish details (for re-decoration)
• Local atmospheric conditions (temperature, humidity, sunlight)

2. Moisture Content & Timber Classification

• Refer IS 399-1963 for trade and botanical names of Indian timbers.
• Appendix A (IS 2338 Part 1) gives painting characteristics of soft/hardwoods.
• Maximum permissible moisture content varies by timber use and climatic zone (refer IS 399).
• Commercial timbers are classified by zonal distribution.

3. Design & Maintenance Principles

• Use terms per IS 707-1958 (wood definitions).
• Maintenance follows Table 3 of IS 2338 Part II (1967): remove unsound work before repair.
• Round off numerical values as per IS 2338 guidelines.

Typical Moisture Content Limits (Indicative)

Summary Mermaid Diagram

flowchart LR
    A[Timber Selection] --> B[Moisture Content Limits]
    B --> C[Design Based on Exposure]
    C --> D[Finish Application]
    D --> E[Maintenance per IS 2338 Part II]

References: IS 399-1963, IS 707-1958, IS 2338 Part II (1967)

IS 2338 Part 1: Surface Preparation Key Points

Surface Preparation Steps (Clauses 6.1, 7.4.3, 11.2)

• Cleaning: Remove all dirt, grease, and loose material.
• Sanding: Rub down with pumice stone or abrasive paper. Sand edges carefully to avoid cutting through.
• Filling:
  • Touch up holes/cracks with primer and undercoat paint.
  • After drying, fill with suitable filler.
• Dust Removal: Blow off dust and wipe surface clean before finishing.
• Drying: Ensure the surface is fully dry before sanding or applying next coats.

Important Specifications (Clause 3.1)

• Provide details on:
  • Wood type and pretreatment (preservation, seasoning).
  • Exposure conditions (weather, location).
  • Finish type (pigmented, clear, etc.).
  • Previous finishes for re-decoration.
  • Local atmospheric conditions (temperature, humidity, sunlight).

Summary Table for Surface Preparation

flowchart TD
    A[Clean Surface] --> B[Sanding with Pumice/Abrasive]
    B --> C[Apply Primer & Undercoat on Cracks]
    C --> D[Fill with Suitable Filler]
    D --> E[Allow to Dry Fully]
    E --> F[Sanding (Avoid Edges)]
    F --> G[Remove Dust & Wipe Clean]
    G --> H[Apply Final Paint Finish]

Note: For detailed paint types, fillers, and finishing procedures, refer to IS 2338 Part II (1967).

Priming, Stopping, and Filling as per IS 2338 (Part 1) - 1967

1. Priming

• Must be done before stopping and filling to prevent shrinkage and falling away of filler/stopping due to binder absorption (Clause 6.3).

2. Stopping and Filling

3. Function of Fillers

• Fill open wood cells to prevent excessive finish penetration.
• Level porous wood surfaces for smooth finishing (Clause 7.2.1).

Summary Table of Materials:

flowchart TD
    A[Priming] --> B[

IS 2338 Part 1 - Staining and Varnishing Operations: Key Points

1. Information Required for Finishing (Clause 3.1)

• Wood type & pretreatment: Preservation, seasoning.
• Location exposure: Weather impact on wood.
• Finish type: Pigmented, clear, etc.
• Previous finish: For re-decoration.
• Atmospheric conditions: Temperature, humidity, sunlight.

2. Protection & Limitations (Clause 3.2)

• Finishes do not protect wood from biological decay.
• Continuous film of finish prevents oviposition by wood-boring insects.

3. Application of Stains (Clause 7.3.6.1)

• Methods: Brushing, wiping, spraying.
• Stain must be thinned for liberal application without over-staining.
• On softwoods, apply evenly without overlapping.
• Spirit stains dry quickly; apply carefully and swiftly.

4. Rounding Off Values (Clause 0.5)

• Use IS 2-1960 rules for rounding numerical test results.
• Maintain significant digits same as specified values.

Typical Staining Application Tips:

flowchart TD
    A[Wood Preparation] --> B[Stain Thinning]
    B --> C{Application Method}
    C -->|Brush| D[Apply Evenly]
    C -->|Wipe| D
    C -->|Spray| D
    D --> E[Drying]
    E --> F{Finish Type}
    F -->|Pigmented| G[Final Coat]
    F -->|Clear| G

Summary: Proper wood prep, knowledge of wood & environment, correct stain thinning, and application method ensure effective staining and varnishing per IS 2338 Part 1.

IS 2338 Part 1 (1967) - French Polish Key Points

Surface Preparation (Clause 8.2)

• Rub surface smooth with sandpaper; remove dust thoroughly.
• Fill pores with filler: whiting paste in water or methylated spirit + pigment (e.g., burnt sienna or umber).
• Proper filling prevents absorption and ensures good gloss.

Application (Clause 7.3.6.2 & 7.5.2.2)

• After staining, apply French polish or wax polish.
• For economy, size the surface before varnishing; allow size to dry thoroughly.
• For durability, apply 2-3 coats of clear varnish after French polishing.

Specifications Summary

Note: Modern clear finishes like nitrocellulose or polyester are not covered by this standard.

flowchart TD
    A[Wood Surface] --> B[Sandpaper Smooth]
    B --> C[Pore Filling with Whiting Paste]
    C --> D[Staining]
    D --> E[French Polish Application]
    E --> F{Finish Type}
    F -->|Economy| G[Size + Varnish (1 coat)]
    F -->|Durability| H[Size + Varnish (2-3 coats)]

IS 2338 Part 1: Finishing of Wood-Based Materials — Key Points

1. Essential Information for Finishing (Clause 3.1)

• Wood Type & Pretreatment: Species, preservation, seasoning.
• Location & Exposure: Indoor/outdoor, weather exposure.
• Finish Type: Pigmented, clear, varnish, paint.
• Previous Finish: For re-decoration purposes.
• Atmospheric Conditions: Temperature, humidity, sunlight intensity.

2. Workmanship & Coordination (Clause 3.3)

• Ensure proper communication between finishers and other trades to avoid defects.

3. General Specifications

• Use preservatives and seasoning appropriate to wood type and exposure.
• Select finishes compatible with wood and environment.
• Follow manufacturer’s recommendations on application methods and drying times.

Typical Finishing Process Overview

flowchart LR
    A[Wood Preparation] --> B[Surface Cleaning]
    B --> C[Preservative Treatment]
    C --> D[Application of Primer]
    D --> E[Main Finish Coats]
    E --> F[Drying & Curing]
    F --> G[Inspection & Touch-up]

Notes:

• IS 2338 Part 1 does not provide explicit formulas or tables but emphasizes information exchange and workmanship standards.
• For thickness of finish coats, drying times, and material specifics, refer to paint manufacturers’ datasheets and IS 2395 (Paints and Varnishes).

Summary:
Successful finishing depends on proper wood selection, environmental assessment, finish compatibility, and coordination among workers. Use IS 2338 Part 1 as a guideline for operations and workmanship rather than specific numeric tables.

IS 2338 Part 1: Inspection and Quality Control Key Points

Inspection Principles (Clause 11.1)

• Follow Table 3 of IS 2338 Part II (1967) for maintenance.
• Remove all unsound paint by burning off or other methods before repainting.

Quality Control During Application (Clause 10.1)

• Confirm correct finishing material, number of coats, and sequence.
• Inspect for:
  • Uniformity of finish and color
  • Complete coverage of substrate
  • Absence of defects: runs, sags, wrinkles, fat edges, dust, bare patches, cracks
  • No tackiness after drying
  • No brush marks or laddering
  • Clean, neat finish

Defect Reporting (Clause 10.1.3)

• Report faults in:
  • Paint consistency
  • Drying time
  • Overall quality of finish

Summary Table: Visual Inspection Criteria

This ensures durability and aesthetic quality per IS 2338 Part 1 standards.

Maintenance as per IS 2338 Part 1 (1967)

• General Principle (Clause 11.1): Follow Table 3 of IS 2338 Part II (1967) for maintenance procedures. Remove all unsound work by burning off or other means before applying new work.

• Paint Failure Diagnosis (Clause 10.1.4): Consider:

  • Surface nature and history
  • Materials used
  • Climatic conditions before/during/after painting
  • Technical correctness of application
  • Workmanship quality

• Information for Efficient Finishing (Clause 3.1):

  • Wood type and pretreatment (preservation, seasoning)
  • Location & exposure to weather
  • Finish type (pigmented, clear, etc.)
  • Previous finish details (for re-decoration)
  • Local atmospheric conditions (temperature, humidity, sunlight)

• Surface Preparation (Clause 6.1): Essential before finishing; ensure clean, dry, and sound surfaces.

Key Table Reference (IS 2338 Part II, Table 3 - Summary for Maintenance)

Summary Diagram

flowchart TD
    A[Inspect Surface] --> B{Defect?}
    B -- Yes --> C[Remove Unsound Work]
    B -- No --> D[Clean Surface]
    C --> D
    D --> E[Apply Primer/Finish]
    E --> F[Monitor Climatic Conditions]

This approach ensures durable maintenance aligned with IS 2338 standards.

Painting Characteristics of Timbers
(IS 2338 Part 1, Appendix A & Clauses 1.1, 3.1, 6.1.1)

Key Points:

• Resinous Softwoods (A-1.1): These may exude resin through paint films and require special treatment:

  Trade Name	Botanical Name
  Chir	Pinus roxburghii Sargent
  Cypress	Cupressus torulosa Don
  Deodar	Cedrus deodara Loudon
  Kail	Pinus wallichiana A. B. Jacks
  Spruce	Picea smithiana Boiss

• Hardwoods: Generally porous and require filling; some with pores <100 microns or filled with gum may not need filling.

• Wood Preparation (Clause 6.1.1):

  • Wood must be well seasoned, free from discoloured sapwood and large resinous/loose knots.
  • Unsound portions should be cut out and replaced.
  • Resinous knots may cause paint exudation and discoloration.

Painting Application Considerations (Clause 3.1):

• Type of wood and pretreatment (seasoning, preservation)
• Location & exposure to weather
• Type of finish (pigmented, clear)
• Previous finish info for redecorating
• Atmospheric conditions (temperature, humidity, sunlight)

Summary Table: Treatment for Resinous Woods

This ensures durable, uniform paint finish and prevents defects like resin bleed, discoloration, and cracking.

flowchart TD
    A[Wood Selection] --> B{Is Wood Resinous?}
    B -- Yes --> C[Special Pretreatment]
    B -- No --> D{Is Hardwood?}
    D -- Yes --> E{Pore Size > 100 microns?}
    E -- Yes --> F[Apply Filler]
    E -- No --> G[No Filler Needed