Code of Practice for Magnesium Oxychloride Composition Floors

IS 658: Scope - Key Specifications & Tables

Scope Summary: IS 658 covers specifications for magnesium chloride floor finishes, including preparation, application, and protection of metalwork involved.

Key Points from Clause 5.11 (Appendix A) – Protection of Metalwork

• Metal surfaces must be clean, rust-free, and free of loose mill scale before coating.
• Use anti-corrosive coatings:
  • Hot application: Bituminous or coal tar compositions.
  • Cold application: Bitumen or coal tar solutions in volatile solvents (exclude drying oil paints).
• Coal tar preparation:
  • Heat crude coal tar to ~120°C until water/volatiles removed.
  • Add hydrated lime (% by weight), stir and heat 30 min.
  • Add fillers (e.g., 5% asbestine) for hot application to resist flow.
• No thinners allowed in compositions.

Table 1: Specific Gravity of Magnesium Chloride Solution (Clause 6.2.1)

Additional Notes

• Concrete base absorption test: Water ponded for 5 min; if fully absorbed, base is too absorbent.
• Use clean water for dissolving magnesium chloride; avoid contamination.
• Prepare solution early; cool to room temperature before use.

This scope ensures durability and corrosion resistance of metal parts and proper preparation of magnesium chloride solutions for floor finishes.

IS 658: Definitions & Terminology - Key Points

1. Definitions (Clause 2.0)

• Standardized meanings for terms related to flooring materials and methods.
• Ensures uniform understanding across applications.

2. Protection of Metalwork (Appendix A, Clause 5.11)

• Metal surfaces must be clean, rust-free.
• Use anti-corrosive coatings:
  • Hot application: Bituminous/coal tar with fillers.
  • Cold application: Bitumen/coal tar solution in volatile solvents (no drying oils).
• Coal tar preparation: Heat to 120°C, add hydrated lime, stir 30 min.
• No thinners allowed.

3. Testing Base Absorption (Appendix B, Clause 6.1.2)

• Create 300 mm × 300 mm × 15 mm reservoir on floor.
• Pour 0.5 pint water; if absorbed within 5 minutes, base is too absorbent.

4. Physical Requirements (Clause 7.2.2)

5. Strength Requirements (Table 2, Clause 7.2.2)

Types of Magnesium Oxychloride Floors (IS 658 Highlights)

1. General Purpose Floor (Trowel Finish) [Clause 3.2]

• Composition: Calcined magnesite + fillers (talc, sawdust, asbestos) + fine aggregates + MgCl₂ solution.
• Characteristics: Dense, smooth, semi-glossy finish.
• Applications: Offices, ship decks, railway carriages, hospitals, residences, industrial floors.

2. Magnesium Chloride Solution Preparation [Clause 6.2.1]

• Use clean water, dissolve MgCl₂ in a watertight vessel.
• Let solution settle overnight, use only clear solution.
• Specific gravity controlled as per Table 1 below.

3. Proportion of Chloride Solution [Clause 6.3.1]

• Add just enough MgCl₂ solution to dampen dry mix.
• Extra solution aids finishing but does not increase strength.
• Excessive MgCl₂ is harmful.

4. Suitability & Precautions [Clause 5.1]

• Not recommended for high humidity/damp or seawater exposure.
• Damp-proof membrane essential if base contacts ground.

flowchart LR
    A[Dry Mix: Magnesite + Fillers + Aggregates] --> B[Add MgCl2 Solution]
    B --> C{Mix Consistency}
    C -->|Sufficient| D[Trowel & Finish]
    C -->|Excess| E[Weak Floor, Avoid]
    D --> F[Dense, Smooth Floor]

Summary: Use MgCl₂ solution with specific gravity 1.14–1.20 depending on coat. Mix proportion carefully for durability. Avoid moisture exposure and ensure damp-proofing.

IS 658: Materials and Composition - Key Points

1. Protection of Metalwork (Appendix A, Clause 5.11)

• Metal surfaces must be clean, rust-free, and coated with anti-corrosive materials.
• Suitable coatings:
  • Hot application: Bituminous/coal tar composition with fillers (e.g., 5% asbestine).
  • Cold application: Bitumen/coal tar solution in volatile solvent (no drying oils).
• Coal tar preparation: Heat crude coal tar to ~120°C, remove volatiles, add hydrated lime, stir 30 min.

2. Magnesium Chloride Solution (Clause 6.2.1, Table 1)

• Prepare solution in watertight vessels, allow impurities to settle overnight.
• Avoid contact of magnesium chloride with floors/walls during preparation.

3. Physical Requirements of Mixes (Clause 7.2.2)

• Setting Time:
  • Initial: 1 to 2 hours
  • Final: 3 to 6 hours
• Strength (N/mm²):

IS 658: Properties & Performance Requirements (Clause 7.2.2)

1. Setting Time (IS 10132-1982)

• Initial Setting Time: 1 to 2 hours
• Final Setting Time: 3 to 6 hours

2. Strength Requirements (Transverse & Compressive Strength in N/mm²)

3. Linear Change Limits

• Expansion: ≤ 0.15%
• Contraction: ≤ 0.25%

Summary Diagram: Performance Requirements Flow

flowchart TD
    A[Mix Sample] --> B[Setting Time Test (IS 10132)]
    B --> C{Setting Time Limits}
    C -->|Initial| D[1 to 2 hours]
    C -->|Final| E[3 to 6 hours]
    A --> F[Strength Test (IS 10132)]
    F --> G[Transverse & Compressive Strength]
    G --> H{Check against Table 2}
    A --> I[Linear Change Test]
    I -->

IS 658: Preparation and Laying of Floor Finish

1. Preparation of Magnesium Chloride Solution (Clause 6.2.1)

• Magnesium chloride must be dissolved in clean water in a watertight vessel.
• Solution should stand overnight for impurities to settle.
• Stir well after each dilution before checking specific gravity.
• Cool solution to room temperature before use.
• Avoid contact with floors/walls during preparation.

2. Specific Gravity of Magnesium Chloride Solution (Table 1)

3. Laying the Floor Finish (Clause 6.5)

• Concrete base must be thoroughly dry before applying the floor finish.

4. Testing of Flooring Composition (Clause 7.2.1)

• Samples should be taken from at least three parts of the mix vessel.
• Mix samples thoroughly before testing.
• For mottled finishes, test each color mix individually.

This ensures durability and proper bonding of the floor finish to the base.

IS 658 - Inspection and Testing Key Points

1. Inspection (Clause 7.1)

• Inspect before, during, and after laying.
• Focus on:
  • Base condition
  • Protection of metalwork (anti-corrosive coatings, clean surface)
  • Correct mixing of materials
  • Proper compaction
  • Adequate curing

2. Protection of Metalwork (Appendix A, Clause 5.11)

• Clean metal surface free of rust/mill scale.
• Use bituminous/coal tar coatings (hot or cold application).
• Coal tar preparation:
  • Heat to ~120°C to remove volatiles.
  • Add hydrated lime (~% by weight).
  • Add fillers (e.g., 5% asbestine) for hot application.
• No thinners allowed.

3. Testing Physical Properties (Clause 7.2.2)

• Setting Time (IS 10132-1982):

• Strength Requirements:

IS 658: Surface Treatment & Maintenance - Key Points

1. Protection of Metalwork (Clause 5.11, Appendix A)

• Surface Preparation: Metal must be clean, rust-free, and free from loose mill scale.
• Coating Types:
  • Hot application: Bituminous or coal tar composition (with fillers like 5% asbestine).
  • Cold application: Bitumen or coal tar solution in volatile solvent (no drying oils).
• Coal Tar Preparation:
  • Heat crude coal tar to ~120°C until water/volatiles removed.
  • Add hydrated lime (% by weight), stir & heat 30 mins.
  • No thinners allowed.

2. Floor Base Absorption Test (Appendix B)

• Build a 300 mm × 300 mm × 15 mm reservoir.
• Pour 0.5 pint water, observe absorption.
• If water absorbed within 5 minutes, floor is unduly absorbent.

3. Magnesium Chloride Solution (Clause 6.2.1, Table 1)

• Prepare solution outside if possible.
• Use clean water; allow solution to settle overnight.
• Maintain specific gravity as above.

4. Surface Treatment (Clause 6.8)

• Remove efflorescence by dry steel wool.
• Wash with clean warm water repeatedly.
• Treat with equal volumes of double boiled linseed oil + turpentine or wax/drying oil.

5. Physical Requirements of Floor Mixes (Clause 7.2.2)

6. Strength Requirements (Table 7.2)

| Floor Type | Transverse Strength (N/mm

IS 658 - Storage of Materials: Key Points & Specifications

1. General Storage Conditions (Clause 9)

• Store materials in clean, dry, and well-ventilated areas.
• Protect metalwork from corrosion using anti-corrosive coatings (Appendix A).

2. Protection of Metalwork (Appendix A, Clause 5.11)

• Clean metal surfaces free from rust and mill scale before coating.
• Use either:
  • Hot application: Bituminous/coal tar composition with fillers (e.g., 5% asbestine).
  • Cold application: Bitumen/coal tar solution in volatile solvent (no drying oils).
• Coal tar preparation: Heat to ~120°C, remove volatiles, add hydrated lime, stir 30 min.

3. Floor Surface Preparation (Clause 8.1)

• Clean floors with warm water; mild alkali-free soap occasionally.
• Avoid soda, cleaning powders.
• Apply wax polish or drying oil dressing after cleaning.

4. Magnesium Chloride Solution (Clause 6.2.1 & Table 1)

• Prepare solution outside or protect floors if inside.
• Specific gravity control critical for floor finish:

5. Testing Floor Absorption (Appendix B)

• Use 300 mm sq × 15 mm deep reservoir.
• Pour 0.25 pint water; if absorbed in 5 mins → floor is too absorbent.

flowchart TD
    A[Material Storage] --> B[Metalwork Protection]
    B --> C[Surface Cleaning]
    B --> D[Anti-Corrosive Coating]
    A --> E[Floor Preparation]
    E --> F[Cleaning]
    E --> G[Wax/ Oil Dressing]
    A --> H[Magnesium Chloride Solution]
    H --> I[Preparation & Specific Gravity Control]
    A --> J[Absorption Test]

Summary: Proper storage involves clean, dry conditions; anti-corrosive treatment for

Protection of Metalwork (IS 658, Clause 5.11, Appendix A)

Key Specifications:

• Surface Preparation: Metal must be clean, free from rust and loose mill scale before coating.
• Coating Requirements: Must form a non-brittle, impervious film over the entire surface.
• Suitable Coatings:
  • Hot Application: Bituminous or coal tar composition, possibly with fillers.
  • Cold Application: Solution of bitumen or coal tar in volatile solvent (excluding bituminous paints with drying oils).

Coal Tar Preparation (for coatings):

Summary Table: Coating Materials

Additional Notes:

• Coatings must adhere well and be impervious to moisture and chemicals.
• Proper preparation ensures durability and corrosion resistance.

flowchart TD
    A[Clean Metal Surface] --> B[Apply Hot Bituminous/Coal Tar Coating]
    A --> C[Apply Cold Bitumen/Coal Tar Solution]
    B --> D[Add Fillers (e.g., Asbestine) for Hot Application]
    C --> E[No Drying Oil Paints Allowed]
    D --> F[Non-brittle, Impervious Coating]
    E --> F

This ensures long-term corrosion protection of metalwork as per IS 658.

IS 658 - Method of Testing the Base for Absorption

Method (Clause 6.1.2, Appendix B):

• Select 3 agreed positions on the concrete floor.
• At each position, create a reservoir 300 mm × 300 mm × 15 mm deep using putty or plasticine walls.
• Pour 0.5 pint (approx. 237 ml) of water into the reservoir.
• Note the time.
• If water is fully absorbed within 5 minutes, the base is considered unduly absorbent.

Key Points:

• Purpose: Ensure base does not absorb magnesium chloride solution excessively, which could affect floor finish.
• Reservoir dimensions: 300 mm square, 15 mm deep.
• Water volume: 0.5 pint.
• Max absorption time: 5 minutes.

Related Specifications:

Additional Notes:

• Protect floors during magnesium chloride solution preparation (Clause 6.2.1).
• Maintain specific gravity of MgCl₂ solution as per Table 1 (1.14 to 1.20 depending on coat).
• Physical and strength requirements of mixes per Clause 7.2.2.

flowchart TD
    A[Select 3 floor positions] --> B[Build 300x300x15 mm reservoir]
    B --> C[Pour 0.5 pint water]
    C --> D[Start timer]
    D --> E{Water absorbed in 5 mins?}
    E -->|Yes| F[Base is unduly absorbent]
    E -->|No| G[Base absorption acceptable]

This test ensures durability and performance of floor finishes by controlling base absorption characteristics.