Specification for steel windows for industrial buildings

IS 1361: Scope - Key Specifications & Tables

Scope Summary:

• Covers steel windows for industrial buildings (factories, warehouses).
• Larger sizes than domestic windows (IS 1038-1975) to suit industrial needs.
• Sizes based on a 100 mm modular system.
• Tolerances per IS 1233-1969.
• 10 mm clearance all around for fitting into modular openings.
• Steel sections per IS 7452-1974 (separate from this standard).

Key Table: Glass Pane Sizes (Clause 11.1)

Important Clauses:

• 6.6: All mild steel fittings (bolts, nuts, screws, washers, peg stays) must be corrosion treated.
• Construction: Coupling details for sash units (steel, aluminum bars) are specified for modular assembly.
• Modular Coordination: Sizes and clearances follow IS 1233-1969 for building industry modular coordination.

Summary Diagram: Modular Window Unit

flowchart LR
    A[Modular Opening] -->|10 mm clearance| B[Steel Window Unit]
    B --> C[Glass Pane (per Table 1 sizes)]
    B --> D[Steel Frame (IS 7452-1974 sections)]
    B --> E[Corrosion treated fittings (Clause 6.6)]

Use this standard for designing and specifying steel windows tailored for industrial buildings with modular coordination and corrosion resistance.

IS 1361 - Key Definitions and Specifications

1. Definitions (Clause 2.0)

• The standard defines terms related to steel windows for industrial buildings.
• It covers sizes, materials, and components specific to industrial use, distinct from domestic standards (IS 1038).

2. Glass Pane Sizes (Clause 11.1, Table 1)

3. Material Specifications

• Bolts, nuts, screws, washers, peg stays, and mild steel fittings must be corrosion treated (Clause 6.6).
• Steel sections follow:
  • Hot rolled steel for doors/windows (IS 7452-1974)
  • Structural steel ordinary and standard quality (various IS codes)
• Screws and bolts follow ISO metric screw thread standards (Parts I-VI).

4. Construction & Coupling (Fig. 2)

• Coupling bars for fixed and open sashes are specified as:
  • 2A: Steel coupling bar
  • 2B: Extruded aluminium alloy coupling bar
  • 2C, 20, 2E: Various sash coupling types

5. Dimensional Tolerances

• Manufacturing sizes based on a 10 cm module, with 10 mm clearance all around for fitting into modular openings.

flowchart LR
    A[Steel Window Unit] --> B[Fixed Sash]
    A --> C[Open Sash]
    B --> D[Coupling Bar 2A (Steel)]
    B --> E[Coupling Bar 2B (Aluminium)]
    C --> F[Coupling of Two Open Sashes (2E)]
    C --> G[Coupling of Fixed & Open Sash (20)]

Summary: IS 1361 defines standard pane sizes, material treatments, coupling methods, and dimensional tolerances for steel windows in industrial buildings, ensuring

IS 1361: Handing and Direction of Closing - Key Points

• Handing & Direction Designation: As per Clause 3.1, sash handing and closing direction follow IS 4043-1969 symbolic designations, e.g.:

  • IN 10 C 20 or IN 10 T 20
  • These codes specify sash type, handing, and closing direction.

• Sash Types & Sizes: Clause 5.1.1 refers to Fig. 1 for standard industrial sash types and sizes (dimensions in cm).

• Glass Panes: Clause 6.4 mandates glass to conform to:

  • IS 2835-1977 (flat transport sheet glass)
  • IS 5437-1969 (wired/figured glass)
  • Glass must have squared corners and straight edges.

• Ventilators (Clause 9.5):

  • Bottom-hung ventilators use steel/malleable iron folding side arms to limit opening (see Fig. 6).
  • Side arms are invisible when closed.
  • Fixing hole centres and glass pane types detailed in Fig. 4.
  • Spring catch and pulley details in Fig. 5.

Summary Table: Handing & Closing Direction Codes (from IS 4043)

Visual Concept (Simplified)

flowchart LR
    A[Handing & Direction] --> B[IS 4043 Designation]
    B --> C[IN 10 C 20]
    B --> D[IN 10 T 20]
    A --> E[Sash Types & Sizes (Fig.1)]
    A --> F[Glass Specs (IS 2835 & IS 5437)]
    A --> G[Ventilator Arms & Fixings (Fig. 4,5,6)]

For detailed sash dimensions and sectional details, refer to IS 1361 Fig. 1 and Fig. 3.

IS 1361: Composite Windows - Key Points

Notations (Clause 4.2)

• IN 10 C 10/IN 10 C 10/IN 10 C 10: Three identical industrial windows coupled horizontally.
• IN 10 C 15/IN 10 C 15 IN 10 C 10/IN 10 C 10: Four windows coupled in a 2x2 grid; top two are IN 10 C 10, bottom two IN 10 C 15.

Size & Tolerances (Clause 10.1)

• Composite windows are dispatched unassembled with coupling components.
• Each coupling member adds max 20 mm to height or width (including tolerances).

Glazing Clips (Clause 9.9)

• Use two spring steel glazing clips per pane.
• Clips conform to Fig. 11 design (spring steel for secure glazing).

Glass Pane Sizes (Clause 11.1)

• Sizes with clearance are in Table 1 (see IS 1361 for exact dimensions).
• Pane numbers and sizes per window type are detailed in Fig. 4.

Summary Table (Example format)

graph TD
A[Single Window Unit] --> B[Coupling Member (+20mm)]
B --> C[Composite Window Assembly]
C --> D[Glass Panes with Spring Clips]

For exact pane sizes and coupling details, refer to Table 1 and Fig. 4 in IS 1361.

IS 1361: Standard Sizes and Tolerances for Industrial Windows

1. Standard Sizes (Glass Pane Sizes - Clause 11.1, Table 1):

2. Tolerances (Clause 5.2):

• Overall dimensions of industrial windows shall not vary by more than ±3 mm.

3. Composite Window Notations (Clause 4.2):

• E.g., IN 10 C 10/IN 10 C 10/IN 10 C 10 means three identical windows coupled horizontally.
• Mixed types can be coupled both horizontally and vertically as per notation.

4. Coupling Details (FIG. 2):

• Coupling bars can be steel (2A) or extruded aluminum alloy (2B).
• Coupling types include fixed-fixed, fixed-open, open-open sashes (2C, 20, 2E).

Summary Formula for Tolerance Check:

[ |D_{actual} - D_{nominal}| \leq 3 \text{ mm} ]

Where (D) = overall window dimension (width or height).

flowchart LR
    A[Single Window] --> B[Composite Window]
    B --> C[Horizontal Coupling]
    B --> D[Vertical Coupling]
    C --> E[Steel Coupling Bar (2A)]
    C --> F[Aluminium Coupling Bar (2B)]
    D --> G[Fixed-Fixed (2C)]
    D --> H[Fixed-Open (20)]
    D --> I[Open-Open (2E)]

Note: All fittings (bolts, nuts, screws) must be corrosion treated (Clause 6.6).

IS 1361: Materials - Key Specifications & Formulas

1. Corrosion Treatment (Clause 6.6):

• All mild steel fittings (bolts, nuts, screws, washers, peg stays) must be suitably corrosion treated to enhance durability.

2. Material Specifications:

• Steel Sections: Hot rolled steel sections per IS 7452 (latest revision).
• Structural Steel: Ordinary quality (first revision) and standard quality (fourth revision).
• Coupling Bars:
  • Steel coupling bars per IS 1361 Fig. 2A (Thickness: 3.15 mm for sheets/flats).
  • Extruded aluminium alloy coupling bars also allowed.
• Pivots & Spring Catches: Must be made of non-ferrous metals.

3. ISO Metric Screw Threads (for bolts/nuts):

• Follow IS parts I to VI for thread profiles, pitch diameters, tolerances, and size limits (diameter range 1 to 39 mm).

4. Glass Pane Sizes (Clause 11.1, Table 1):

Summary Diagram of Coupling Bars & Materials

graph LR
A[Mild Steel Fittings] -->|Corrosion Treated| B[Bolts, Nuts, Screws, Washers]
C[Coupling Members] --> D[Mild Steel Sheets/Flats (3.15 mm)]
C --> E[Extruded Aluminium Alloy Sections]
F[Pivots & Spring Catches] -->|Non-ferrous Metal| G[Brass, Bronze, etc.]

Note: Use IS 226-1975 for mild steel sheets/flats specifications and IS 1038 for domestic steel windows as a reference for smaller sizes. Always ensure corrosion treatment and adherence to modular coordination per IS 1233-1969.

IS 1361: Fabrication and Welding Key Points

1. Welding Requirements (Clause 7.2.1)

• Permitted welding methods: Any welding method is allowed for corner joints if joints meet the standard's quality requirements.
• Fillet weld test (7.2.1.3):
  • Fillet welds must be fractured by hammering.
  • Fracture surfaces should be free from:
    • Slag inclusions
    • Porosity
    • Cracks
    • Penetration and fusion defects

2. Corrosion Treatment (Clause 6.6)

• All mild steel fittings (bolts, nuts, screws, washers, peg stays) must be suitably corrosion treated.

3. Rounding Off Values (Clause 0.5)

• Final test or analysis values must be rounded as per IS 2:1960, maintaining the same number of significant digits as specified.

Typical Fillet Weld Quality Checks

Summary Diagram of Weld Inspection

flowchart TD
    A[Fabricated Weld Joint] --> B{Fillet Weld Test}
    B -->|Hammer Fracture| C[Inspect Fracture Surface]
    C --> D{Defects?}
    D -->|No| E[Weld Accepted]
    D -->|Yes| F[Weld Rejected]

For detailed dimensions and coupling bar specifications, refer to Fig. 2 in IS 1361.

IS 1361: Fixing Holes and Glazing Clips – Key Points

1. Fixing Holes (Clause 8.1 & 8.2)

• Diameter: 8 mm
• Type: Countersunk holes
• Location: In the web of outside frame sections, 10-40 mm from the outside face (see Fig. 4).
• Glazing clip holes: One hole in the web or tec on each side of each pane.

2. Fixings for Sashes (Clause 9.7)

• Use slotted reversible steel lugs (holdfasts) for brickwork (Fig. 9).
• Fixing options:
  • Countersunk steel nuts & bolts for brickwork.
  • Wood screws for wood, plugged concrete, or stone.
  • Steel screws or mild steel fixing clips with nuts & bolts for steel (Fig. 10).

3. Glazing Clips (Clause 9.9)

• Quantity: Two spring glazing clips per pane.
• Material: Spring steel.
• Design: As per Fig. 11 (spring action to hold glass firmly).

Summary Table:

flowchart TD
    A[Frame Section] --> B[Fixing Holes (8mm countersunk)]
    B --> C[Fixing Lugs (Brickwork)]
    B --> D[Fixing Clips (Steel Work)]
    E[Pane] --> F[Glazing Clip Holes (Web/tec)]
    F --> G[Spring Steel Glazing Clips (2 per pane)]

This ensures secure fixing of sashes and glass panes per IS 1361 specifications.

IS 1361: Fittings and Fixing Materials - Key Points & Specifications

Corrosion Treatment (Clause 6.6)

• All bolts, nuts, screws, washers, peg stays, and mild steel fittings must be suitably corrosion treated (e.g., galvanizing, painting).

Fixing Fittings (Clause 9.7)

• Fixing fittings for sashes include:
  • Slotted reversible steel lugs (holdfasts) with countersunk steel nuts and bolts for brickwork.
  • Wood screws for wood or plugged concrete/stone.
  • Steel screws or mild steel fixing clips with steel nuts and bolts for steel structures.

Coupling Bars & Details

• Types: Steel coupling bar, extruded aluminium alloy coupling bar.
• Coupling arrangements cover fixed and open sashes (Fig. 2).
• All dimensions are in millimeters.

Holes for Glazing Clips (Clause 8.2)

• Holes must be provided in the web of the section on each side of each pane.

Typical Fixing Components Dimensions (from Figures 9 & 10)

Reference Standards for Fittings & Fixings

• IS 1361 refers to:
  • IS 7452-1974 for hot rolled steel sections.
  • IS 1038-1975 for steel doors/windows in domestic buildings.
  • ISO metric screw threads (Parts I-VI) for bolts and nuts specifications.

Summary Diagram of Fixing Types

graph TD
    A[Sash Fixing Fittings] --> B[Brickwork]
    A --> C[Wood or Concrete]
    A --> D[Steel Work]

    B --> E[Slotted Steel Lugs + Nuts & Bolts]
    C --> F[Wood Screws]
    D --> G[Steel Screws or Mild Steel Clips + Nuts & Bolts]

Note: Use corrosion-resistant finishes and ensure all fixing holes and fittings conform to the dimensions and tolerances specified in IS 1361 and referenced IS codes.

IS 1361: Composite Window Assembly - Key Points

Notations (Clause 4.2)

• IN 10 C 10/IN 10 C 10/IN 10 C 10: Three identical industrial windows (type IN 10 C 10) coupled horizontally.
• IN 10 C 15/IN 10 C 15 IN 10 C 10/IN 10 C 10: Four windows; two IN 10 C 15 on top and two IN 10 C 10 below, coupled horizontally and vertically.

Dimensions & Tolerances (Clause 10.1)

• Composite windows dispatched unassembled with coupling components.
• Each coupling member adds max 20 mm to overall height/width (including tolerances).

Glazing Clips (Clause 9.9)

• Provide two spring glazing clips per panel.
• Clips made of spring steel as per design in Fig. 11.

Glass Sizes (Clause 11.1)

• Glass pane sizes per Table 1 (includes clearance).
• Number and sizes per window type shown in Fig. 4.

Typical Glass Size Table (Example format)

(Refer IS 1361 Table 1 for exact sizes)

graph TD
  A[Composite Window] --> B[Individual Window Units]
  B --> C[IN 10 C 10]
  B --> D[IN 10 C 15]
  A --> E[Coupling Members (+20mm)]
  A --> F[Spring Glazing Clips (2 per panel)]

Summary: Use IS 1361 notations for assembly, allow 20 mm per coupling for sizing, use spring steel clips, and refer to Table 1/Fig. 4 for glass pane sizes.

IS 1361 - Glass Panes Key Specifications & Sizes

1. Glass Pane Sizes (Clause 11.1, Table 1)

• Sizes include clearance.
• Number and arrangement per window type are shown in Fig. 4 (not included here).

2. Glass Quality (Clause 6.4)

• Minimum weight: 7.5 kg/m².
• Must be free from flaws, specks, and bubbles.
• Corners must be squared; edges straight.
• Conformance to:
  • IS 2835-1977 (Flat transport sheet glass)
  • IS 5437-1969 (Wired and figured glass)

3. Additional Notes

• Glass panes are used in center-hung, top-hung, and bottom-hung sash windows (see Fig. 3 for sectional details).

Summary Diagram: Glass Pane Size Reference

graph LR
  A[Glass Pane Sizes] --> B[Width: 269-304 mm]
  A --> C[Height: 425-492 mm]
  A --> D[Weight ≥ 7.5 kg/m²]
  A --> E[Conforms to IS 2835 & IS 5437]
  A --> F[Properly squared corners & straight edges]

This concise info helps select and verify glass panes per IS 1361 requirements.

IS 1361: Surface Treatment and Finishes Key Points

• Clause 6.6: All mild steel fittings (bolts, nuts, screws, washers, peg stays) must be corrosion treated.

• Clause 12.1:

  • Steel surfaces must be cleaned (pickling/phosphating) to remove rust, scale, dirt.
  • Then apply two coats of red oxide primer (IS:102-1962) before dispatch.
  • Alternatively, use galvanization (hot dip, zinc spray, electrogalvanizing).

• Clause 12.2:

  • Hot-dip galvanized materials must be dispatched unpainted.
  • Zinc sprayed and electrogalvanized materials require one coat of red oxide paint.

Summary Table: Surface Finishing Requirements

Important Specification References:

• IS:102-1962 - Red oxide primer paint specification
• Corrosion treatment ensures durability and protection of mild steel fittings.

flowchart LR
    A[Steel Surface] --> B{Surface Cleaning}
    B -->|Pickling/Phosphating| C[Apply Red Oxide Primer]
    C --> D[2 Coats Paint]
    B -->|Galvanizing| E{Type of Galvanizing}
    E --> F[Hot Dip Galvanizing]
    F --> G[Dispatch Unpainted]
    E --> H[Zinc Spray / Electrogalv]
    H --> I[1 Coat Red Oxide Paint]

This ensures long-lasting corrosion resistance for steel components in doors, windows, and ventilators as per IS 1361.

IS 1361: Marking and Identification Key Points

• Clause 13.1.1:
  Products may be marked with the Standard Mark indicating conformity to IS 1361.

• Clause 13.1.2:
  Use of the Standard Mark is regulated by the Bureau of Indian Standards Act, 1986. Licensing details are available from BIS.

• Marking Requirements (general practice from IS codes):

  • Manufacturer's name or trademark
  • IS code number (IS 1361)
  • Batch or heat number for traceability
  • Date of manufacture

• Glass Pane Sizes (Clause 11.1, Table 1):

  Pane	Width (mm)	Height (mm)
  &	269	425
  b	304	425
  C	292	460
  d	304	460
  e	304	492
  f	292	492

• Corrosion Treatment (Clause 6.6):
  All mild steel fittings (bolts, nuts, screws, washers, peg stays) must be suitably corrosion treated.

Summary Diagram: Marking Flow

flowchart LR
    A[Product Manufactured] --> B[Mark with Manufacturer ID]
    B --> C[Mark IS Code (IS 1361)]
    C --> D[Mark Batch/Heat Number]
    D --> E{Use Standard Mark?}
    E -->|Yes| F[Apply Standard Mark (per BIS rules)]
    E -->|No| G[No Standard Mark]

For detailed licensing and marking conditions, consult the Bureau of Indian Standards.

IS 1361: Packing and Dispatch Key Points

Clause 14: Packing and Dispatch

• 14.1 Industrial windows: Dispatch with opening parts securely fixed to maintain alignment during fixing and glazing.
• 14.2 Fixing lugs, coupling fittings, and hardware: Dispatched separately to avoid damage and loss.
• 14.3 Composite windows: Dispatched uncoupled to prevent damage during transport.

Summary Table: Packing & Dispatch

Additional Notes:

• Proper packing ensures damage-free transport.
• Separate dispatch of hardware prevents loss and damage.
• Composite windows uncoupled to avoid stress and distortion.

If you need glass pane sizes for packing reference, see below:

For detailed queries, contact BIS offices listed in the code.