IS 4923 Hollow Section Dimensions, Weight and Grade Chart

IS 4923 hollow section dimensions are specified by the Bureau of Indian Standards for square hollow sections (SHS) and rectangular hollow sections (RHS) used in structural fabrication. The standard covers outside dimension, wall thickness, cross-sectional area, and weight per metre for every standard size — the data you need without hunting through a BIS PDF.

What IS:4923 Covers — and How It Differs from IS:1239

IS:4923:1997 is the Indian standard for structural hollow sections — SHS and RHS made by hot forming, electric resistance welding, or seamless process. It is not a pipe standard. IS:1239 covers circular pipes for water and gas; IS:4923 covers square and rectangular structural tubes for columns, frames, trusses, and fabricated structures.

The key practical difference: IS:4923 sections are specified by outside dimension (e.g. 100×100 mm), not by nominal bore. Wall thickness options are defined per size, and the grade system (YST 210 to YST 355) indicates the yield strength of the steel, not the pipe class. Brands like Tata Structura and APL Apollo manufacture to IS:4923 and stamp the grade on the section.

IS:4923 YST Grade Guide

Fabricators frequently order hollow sections without specifying the YST grade, then discover the supplier has defaulted to the lowest available. Here is what each grade means and when to use it:

Mechanical properties as per IS:4923:1997 Table 1. IS 4923 ke anusar YST 310 grade structural frames ke liye recommended hai — always specify grade in your purchase order to avoid receiving YST 210 on structural work.

IS:4923 SHS Weight Chart — Square Hollow Sections

The table below lists standard SHS sizes per IS:4923 with wall thickness options and tabulated weight per metre. These values are calculated using the formula: Weight (kg/m) = 0.0317 × t × (2B − 2t), where B is outside dimension in mm and t is wall thickness in mm — the IS:4923 constant 0.0317 is derived from steel density 7850 kg/m³.

* 100×100×4 mm used in worked example below. Dimensions and weights as per IS:4923:1997 Tables 2 and 3. Mass tolerance: ±6% per individual piece as per IS:4923 Clause 10. Verify actual dimensions with mill test certificate before use in structural calculations.

IS:4923 RHS Weight Chart — Rectangular Hollow Sections

Dimensions and weights as per IS:4923:1997 Table 4. Mass tolerance: ±6% per individual piece, ±4% per consignment of 10 tonnes or more, as per IS:4923 Clause 10. Cross-section area values are for reference; use mill test certificate for structural design.

Weight Formula for IS:4923 Hollow Sections

To calculate hollow section ka weight for any size not in the table above, use the formula derived from IS:4923 geometry:

For SHS: Weight (kg/m) = 4 × t × (B − t) × 7.85 / 1000

For RHS: Weight (kg/m) = 2 × t × (B + H − 2t) × 7.85 / 1000

B

Outside width of section, in millimetres (for SHS: B = H)

H

Outside height of section, in millimetres (RHS only)

t

Wall thickness, in millimetres — as per IS:4923 Table 2 for the specified size

7.85

Density of structural steel in g/cm³ (7850 kg/m³) — constant for all IS:4923 grades regardless of YST designation

1000

Unit conversion factor (mm² × g/cm³ → kg/m)

Use our free Hollow Section Weight Calculator to compute weight instantly for any SHS or RHS dimension — no manual formula needed.

Worked Example — 100×100×4 SHS for a Canopy Frame

A fabricator in Pune is designing a pedestrian canopy support frame. Each column uses 100×100×4 mm SHS in YST 310 grade (Tata Structura). He needs the total dead load contribution from 12 metres of hollow section per column to complete his load calculation.

Step 1 — Read weight from IS:4923 table:
100×100×4 mm SHS = 11.97 kg/m (from the SHS table above)

Step 2 — Calculate total section weight per column:
11.97 kg/m × 12 m = 143.6 kg

Step 3 — Add fabrication wastage for procurement:
143.6 × 1.10 = 158 kg (10% wastage for cuts and off-cuts)

Step 4 — Convert to stock lengths for ordering:
Tata Structura supplies 100×100×4 in 6-metre random lengths. Each length weighs 11.97 × 6 = 71.82 kg.
Pieces required: 12 m ÷ 6 m = 2 lengths per column. For a 10-column frame: 20 lengths = 1,436 kg total (before wastage).

The ±6% IS:4923 mass tolerance means actual received weight could vary between 1,350 kg and 1,522 kg for this order — always add a buffer when specifying procurement quantities.

For a quick cross-check, see the Tata Structura hollow section weight chart and the APL Apollo hollow section weight chart — both manufactured to IS:4923.