Steel Door Frames

IS 4351 - Steel Door Frames: Scope & Key Specifications

Scope

• Covers material, dimensions, and construction of steel door frames for internal & external use.
• Includes mild steel (1.25/1.60 mm thick), galvanized steel (1.00/1.25/1.60 mm), and stainless steel (1.00 mm).
• Permits powder coatings and introduces two new profiles.
• Installation guidance in Annex A.
• Compliance rounding as per IS 2:1960.

Materials (Table 1)

Profiles for Door Frames (Table 2)

Hinges (Table 3)

Sampling & Defectives (Table 4)

| Lot Size | Sample Size | Perm

IS 4351: Referenced Standards & Key Specifications Summary

Referenced Indian Standards (IS) for Steel Door Frames:

Material Specifications for Door Frames (Clause 5, Table 1)

Hinges for Door Frames (Clause 10.2, Table 3)

IS 4351: Definitions & Key Specifications for Steel Door Frames

Definitions

• Refer to IS 10428 for standard door-related terms.
• Door handing and closing direction per IS 4043.

Materials for Door Frames (Clause 5, Table 1)

Standard Profiles for Door Frames (Clause 7.1.1, Table 2)

Designation System (Clause 6.3)

• P = Pressed steel frame
• Profiles: A, B, C, D, E
• Format: Width-module - Profile - Height-module (e.g., 8-PA-21)

Summary Diagram

graph TD
A[Door Frame] -->|Material| B[Mild Steel (IS 513)]
A --> C[Galvanized Steel (IS 277)]
A --> D[Stainless Steel (IS 6911)]
A --> E[Profiles]
E --> F[A (90x60, Single Rebate)]
E --> G[B (105x60, Single Rebate)]
E --> H[C (125x60, Single Rebate)]
E --> I[D (125x60, Double Rebate)]
E --> J[E (165x60, Double Rebate)]

Notes

• Final test values rounded

IS 4351: Materials for Steel Door Frames

Key Material Specifications (Clause 5, Table 1)

• Mild Steel Sheets: Cold-rolled, thickness 1.25 or 1.60 mm.
• Galvanized Steel Sheets: Zinc coating 120 g/m² both sides, lock forming grade.
• Stainless Steel: Grade X07Cr17 (430) or X04Cr19Ni9 (304 S1).

Additional Notes:

• Mild steel sheets of 1.60 mm thickness are permitted.
• Powder coatings are allowed as per IS 13871.
• Hinges and hardware must conform to relevant IS codes (e.g., IS 1341 for steel butt hinges).
• Painting and pretreatment should follow IS 1477 parts 1 & 2.
• All materials must comply with tolerances and quality checks per IS 4351.

Summary Diagram

graph TD
  A[Steel Door Frames] --> B[Mild Steel Sheet]
  A --> C[Galvanized Steel Sheet]
  A --> D[Stainless Steel Sheet]
  B -->|Thickness| B1[1.25 / 1.60 mm]
  C -->|Thickness| C1[1.00 / 1.25 / 1.60 mm]
  D -->|Thickness| D1[1.00 mm]
  B --> IS513
  C --> IS277
  D --> IS6911

Use IS 2:1960 for rounding off test results.
Refer to Annex A for installation guidance.

IS 4351: Dimensions and Tolerances for Steel Door Frames

1. Material Thickness (Clause 1.60 & Table 1):

• Mild steel sheet (cold rolled): 1.25 mm / 1.60 mm
• Galvanized steel sheets (GPL): 1.00 / 1.25 / 1.60 mm
• Stainless steel (Grade X07Cr17 or X04Cr19Ni9): 1.00 mm

2. Dimensional Tolerances (Clause 7.1):

• ± 1 mm tolerance on all profile dimensions.

3. Frame Size (Clause 6.1.1):

• Overall height and width are measured outside the pressed steel frame.
• Includes 5 mm clearance on all four sides for fitting into modular openings.

4. Hinges Specifications (Clause 10.2 & Table 3):

Summary Table: Key Dimensions & Tolerances

Notes:

• Final test values should be rounded as per IS 2:1960.
• Refer to Annex A for installation recommendations.
• Profiles designated by letters (A, B, C, D, E) with 'X' in naming.
• Use relevant IS standards for hinges and hardware fittings.

IS 4351: Profiles and Designations for Steel Door Frames

Profiles (Clause 7.1.1 & Table 2):

• Profiles suit doors opening inward/outward.
• Frame parts: hinge jamb, lock jamb, head, steel base ties.
• Frames welded or mechanically fixed.

Designation (Clause 6.3):

• Format: [Width]-P[Profile]-[Height]
• P = Pressed steel door frame
• Profiles: A, B, C, D, E

Example: 8-PA-21 means width 8 modules, pressed steel, profile A, height 21 modules.

Material (Clause 5, Table 1):

Summary Diagram of Profiles

graph LR
    A[Profile A: 90x60 Single Rebate]
    B[Profile B: 105x60 Single Rebate]
    C[Profile C: 125x60 Single Rebate]
    D[Profile D: 125x60 Double Rebate]
    E[Profile E: 165x60 Double Rebate]

Note: Refer to Annex A for installation guidance and IS 4043 for door handing and closing direction designation.

IS 4351: Steel Door Frames - Key Construction Specifications

Materials (Clause 5, Table 1)

Hinges (Clause 10.2, Table 3)

Installation Guidelines (Annex A, Clause 1.1)

• Position frame at correct height & plumb.
• Use temporary struts to prevent bowing/sagging.
• Build walls solid on both sides with cement grout (1:3:6 volume).
• Provide 3 lugs per jamb, max 750 mm apart.
• Remove temporary struts only after brickwork sets.
• If base tie screws are used, remove after floor laying.

Additional Notes

• Mild steel sheets of 1.60 mm thickness permitted.
• Powder coatings allowed (see IS 13871).
• Follow IS 2:1960 for rounding off test values.
• Use IS 4043 for door handing & closing directions.

flowchart TD
    A[Select Material] --> B{Material Type}
    B -->|Mild Steel| C[Use 1.25/1.60 mm IS 513]
    B -->|Galvanized Steel| D[Use 1.00/1.25/1.60 mm IS 277]
    B -->|Stainless Steel| E[

Fixing Lugs (Holdfasts) - IS 4351 Key Points

• Quantity:

  • 3 adjustable lugs per jamb without fanlight.
  • 4 adjustable lugs per jamb with fanlight.
    (Clause 10.1)

• Dimensions (Length Y in mm) for Holdfast Tail (Table 10.1.3):

• For fixing to R.C.C. columns, tail length ≥ 300 mm with holes for plumbing nails.
  (Clause 10.1.3 & Fig. 4B)

• Material: Steel strips conforming to IS 513 or IS 277.
  (Clause 10.1.4)

• Surface treatment: Paint with red oxide zinc chromate primer as per IS 2074.
  (Clause 10.1.5)

Diagram: Fixing Lug to Frame and RCC Column

flowchart LR
    A[Door Frame] -->|Fixing Lug (Holdfast)| B[RCC Column or Masonry]
    B --> C[Plumbing Nails through holes]
    style A fill:#f9f,stroke:#333,stroke-width:2px
    style B fill:#bbf,stroke:#333,stroke-width:2px

Summary: Use 3 or 4 adjustable steel lugs per jamb, sized per profile with specified tail lengths, painted with primer, and fixed securely with plumbing nails to masonry or RCC columns.

Base Ties as per IS 4351

• Material & Size: Pressed mild steel angle, 20 mm × 20 mm × 1.25 mm thick.
• Purpose: To suit floor thicknesses of 25, 30, 35, or 40 mm.
• Fixing: Either screwed or welded at the base of door frames (Fig. 3).

Key Dimensions & Profiles (Clause 7.1.1 & Table 2)

Fixing Lugs (Holdfasts) to RCC Columns (Clause 10.1.3 & Table)

• Tail length: Minimum 300 mm with holes for plumbing nails.
• Dimension Y varies by profile:

Summary Diagram of Base Tie Fixing

graph LR
A[Pressed Steel Angle 20x20x1.25mm] --> B[Welded or Screwed to Frame Base]
B --> C[Fixed to Floor (25-40 mm thick)]
B --> D[Connected to Holdfast Lug]
D --> E[Holdfast Tail (min 300 mm) with Holes]
E --> F[RCC Column]

Note: Base ties ensure structural integrity at the door base, connecting the frame rigidly to the floor and adjacent RCC columns via holdfasts.

IS 4351: Fittings and Hardware for Steel Door Frames

Key Hinges Specifications (Clause 10.2, Table 3)

Materials for Door Frames (Clause 5, Table 1)

Fixing Lugs (Holdfasts) (Clause 10.1.3)

• Tail length for RCC fixing lugs: minimum 300 mm with holes for plumbing nails.
• Dimension 'Y' varies by profile (A to E): 85 to 160 mm (±1 mm tolerance).

Additional Notes

• Hardware handing and door closing directions per IS 4043.
• Painting and coatings per IS 1477 and IS 13871 (powder coatings).
• Use slotted countersunk screws as per IS 1365.
• Sampling and defect limits per Table 4 (Clause B-1.3).

Summary Diagram: Door Frame with Hinges & Fixing Lugs

graph LR
A[Steel Door Frame] --> B[Hinges (IS 1341 / 12817 / 9106 etc.)]
A --> C[Fixing Lugs / Holdfasts]
B --> D[Door Shutter]
C --> E[RCC Column or Masonry]

**For detailed design, always refer

IS 4351 - Surface Treatment & Finishing of Steel Door Frames

Key Specifications:

1. Pre-treatment & Phosphating (Clause 11.1):

   • Surface of steel frames must undergo pre-treatment and phosphating to improve paint adhesion and corrosion resistance.

2. Painting (Clause 11.2):

   • Two coats of ready mixed, air-drying red oxide zinc chrome primer (per IS 2074) applied by brushing, spraying, or dipping as per IS 1477 (Part 2).
   • Alternative paints allowed if agreed upon.

3. Powder Coating (Clause 11.3):

   • After phosphating, powder coating conforming to IS 13871 is permitted.
   • Colour selected from indigenous powder manufacturer’s shade card, mutually agreed.

Material Thickness (Table 1):

Summary Flow for Surface Treatment:

flowchart LR
    A[Steel Frame] --> B[Pre-treatment & Phosphating]
    B --> C{Choose Finish}
    C --> D[Paint: 2 Coats Red Oxide Zinc Chrome Primer]
    C --> E[Powder Coating as per IS 13871]
    D --> F[Final Finish]
    E --> F

References for further details:

• IS 1477 (Part 2) — Painting procedure
• IS 2074 — Primer paint specification
• IS 13871 — Powder coating specification

This ensures corrosion resistance, durability, and aesthetic finish for steel door frames.

IS 4351: Marking and Certification Key Points

BIS Certification Marking (Clause 12.2)

• Steel door frames may bear the BIS Standard Mark under the Bureau of Indian Standards Act, 1986.
• License for use of the Standard Mark is governed by BIS rules.
• Sampling and conformity criteria are detailed in Annex B.
• Purchaser must provide ordering details as per Annex C.

Sampling & Conformity (Annex B)

• A frame failing any tested requirement is defective.

Material Specifications (Table 1, Clause 5)

Information to be Supplied by Purchaser (Annex C)

• Frame designation, size, profile
• Door opening direction (for external doors)
• Door handing
• Location/type of locks, aldrop, tower bolts
• Door shutter thickness

Summary Diagram: Certification & Ordering Flow

flowchart TD
    A[Manufacturer] --> B[Apply for BIS License]
    B --> C[Use Standard Mark on product]
    C --> D[Sampling & Inspection per Annex B]
    D -->|Pass| E[Product Certified]
    D -->|Fail| F[Product Rejected]
    G[Purchaser] --> H[Provide Ordering Info as per Annex C]
    H --> A

**Note

IS 4351: Sampling and Inspection of Steel Door Frames

Sampling Procedure (Annex B & Clauses 1.3, 1.4)

• Lot Definition: Frames of same size, profile, designation, and production conditions form a lot.
• Sample Size: Number of frames to inspect depends on lot size (see Table 4 below).
• Random Selection: Samples must be randomly selected as per IS 4905 to ensure unbiased inspection.

Table 4: Number of Frames to be Selected from Lot

(Note: Refer IS 4351 Annex B for exact values and details)

Inspection Criteria

• Samples are tested for dimensional accuracy, material quality, and workmanship.
• Conformity criteria are specified in Annex B of IS 4351.
• Use of BIS Standard Mark requires adherence to BIS Act 1986 (Clause 12.2.1).

Installation Highlights (Clause 1.1)

• Position frame at correct height and plumb.
• Use temporary struts to prevent bowing/sagging.
• Provide 3 lugs per jamb, max 750 mm apart.
• Build walls solidly with cement grout (1:3:6).
• Remove struts only after brickwork sets.

flowchart TD
    A[Lot of Steel Door Frames] --> B[Group by size & profile]
    B --> C[Determine lot size]
    C --> D[Select sample size (Table 4)]
    D --> E[Randomly select samples (IS 4905)]
    E --> F[Inspect samples for conformity]
    F --> G{Pass?}
    G -->|Yes| H[Accept lot]
    G -->|No| I[Reject or re-inspect]

Summary: Use Table 4 for sample size, follow IS 4905 for randomness, and inspect as per Annex B

IS 4351: Information to be Supplied by Purchaser (Annex C)

When ordering steel door frames, the purchaser must clearly specify:

• Designation, size, and profile of door frame (refer Table 2, Clause 7)
• For external doors, whether the door opens inwards or outwards
• Handing of the door (left or right)
• Type and location of hardware: lock, aldrop, tower bolts, etc.
• Thickness of door shutter

Key Tables and Profiles (Clause 7, Table 2)

Material Specifications (Clause 5, Table 1)

Sampling & Conformity (Annex B, Table 4)

This ensures clarity in manufacturing and quality control per IS 4351.

IS 4351: Installation Recommendations for Pressed Steel Door Frames

Key Installation Guidelines (Clause 1.1, Annex A)

• Positioning: Place frame at correct height from finished floor level.
• Alignment: Ensure frame is plumb, square, and free from twists.
• Temporary Struts: Fix temporary cross struts to prevent bowing or sagging during fixing and subsequent work.
• Wall Filling: Build walls solid on each side of frame; fill gaps with cement grout (1:3:6 by volume).
• Lugs: Provide 3 lugs per jamb, spaced ≤ 750 mm apart.
• Strut Removal: Remove temporary struts only after brickwork sets.
• Base Tie: If screwed base tie is used, leave until floor is laid, then remove.

Material Specifications (Table 1, Clause 5)

Frame Sizes & Tolerances (Clause 6.1.1)

• Overall height and width are external dimensions.
• Allow 5 mm clearance on all sides for fitting into modular openings.
• Profiles designated as A, B, C, D, E (e.g., 900x2100 mm A-profile).

Summary Diagram: Installation Steps

flowchart TD
    A[Place frame at correct height] --> B[Check plumb & square]
    B --> C[Fix temporary struts]
    C --> D[Build walls solid & grout]
    D --> E[Install lugs (3 per jamb, ≤750 mm apart)]
    E --> F[Wait for brickwork to set]
    F --> G[Remove temporary struts]
    G --> H[Remove base tie after floor laid]

For detailed hardware specs, hinge types, and painting, refer to IS 205, IS 1341, IS 1477, and IS 13871.