How we supply it: Structural sections are arranged through a partner steel trader or fabricator who quotes, supplies and bills them and pays us a referral commission. Send the section list from your drawing; we pass it on unchanged and can bring the sections with a TMT load from our yards when the timing suits.
In one line: Structural steel is hot-rolled or cold-formed steel in standard shapes such as I-beams, channels, angles and hollow sections, used to carry loads as members rather than as reinforcement inside concrete.
Structural sections vs TMT bars
Structural steel is hot-rolled or cold-formed steel in standard shapes such as I-beams, channels, angles and hollow sections, used to carry loads as members rather than as reinforcement inside concrete.
TMT bars to IS 1786 work inside concrete. Sections work on their own, bolted or welded into frames, so their shape and weight per metre matter as much as the steel grade.
Section names on a fabricator's list
ISLB, ISWB and ISHB are the light, wide-flange and heavy beam series. The number after the name, as in ISMB 150, is the depth in millimetres.
| Name | Shape | Standard | House-site use |
|---|---|---|---|
| ISMB (Indian Standard Medium weight Beam) | I-beam | IS 808 sizes, IS 2062 steel | Mezzanine and shed beams, wide openings |
| ISMC (Indian Standard Medium weight Channel) | C-channel | IS 808 sizes, IS 2062 steel | Purlins, staircase stringers, gate frames |
| ISA (Indian Standard Angle) | L-angle | IS 808 sizes, IS 2062 steel | Roof trusses, brackets, grill frames |
| Flats and plates | Flat bar, sheet | IS 2062 | Base plates, gussets, grill bars |
| Hollow sections (SHS, RHS) | Square or rectangular tube | IS 4923 | Gates, canopies, light roof frames |
| Structural tubes (CHS) | Round pipe | IS 1161 | Shed columns, handrails |
Grade E250 or higher?
IS 2062 names grades by yield strength: E250 yields at 250 MPa, E350 at 350 MPa. Sheds, staircases and gates for houses are routinely designed in E250.
Within a grade, quality letters (A, BR, B0, C) describe impact toughness and weldability. Buy the letter your drawing names.
| Grade | Minimum yield strength | Where it fits |
|---|---|---|
| E250 (old Fe 410 W) | 250 MPa | Sheds, staircases, gates, light frames |
| E350 | 350 MPa | Longer spans where the design calls for it |
| E450 and above | 450 MPa or more | Industrial and heavy structures |
Weight decides the bill
Typical estimate: steel weighs 7,850 kg/m³, so weight per metre is about cross-section area in cm² × 0.785 kg. Use the standard's tables for exact figures.
Fabricators quote by the kilo. Ask for the section list with lengths and the total weight before cutting starts.
- 50 × 50 × 5 mm angle: about 3.8 kg/m
- 40 × 40 × 2 mm square hollow section: about 2.3 kg/m
- 50 × 6 mm flat: about 2.4 kg/m
Checks when sections arrive
- Measure depth, flange width and thickness with a tape and vernier against the section list.
- Weigh a full length or read the weighbridge slip, and compare with the standard weight per metre.
- Ask for the mill test certificate or marking showing IS 2062 and the grade.
- Reject sections with laminations, deep pitting or bends that will not straighten.
- For hollow sections, check wall thickness at a cut end, not just the outside size.
Storage and rust protection
- Stack on timber sleepers with a slight slope so rainwater runs off.
- Leave hollow-section ends open to drain, or cap them.
- Near the coast, wire-brush loose mill scale and apply a rust-inhibiting primer within days of delivery.
- Keep bolts and base plates in a closed box, not on the ground.
Fabrication mistakes on house jobs
- Swapping in a lighter 'similar' section without the engineer's approval.
- Welding galvanised sections without grinding off the zinc and repainting the joint.
- Skipping primer on parts that will be hidden, such as truss tops under sheets.
- Fixing base plates to pedestals that have not cured.
- Ordering by number of lengths instead of a section list with weights.