IS 2502:1963 Part 1 is the Indian Standard (BIS) for bending and fixing of bars for concrete reinforcement - fabrication. This standard provides comprehensive guidelines for the correct cutting, bending, and fixing of steel reinforcement bars used in reinforced concrete. It specifies the standard dimensions for hooks, bends, stirrups, and ties, along with permissible tolerances, forming the basis for Bar Bending Schedules (BBS).
Lays down the recommended practice for bending and fixing of steel reinforcement bars in concrete construction.
Quick Reference — IS 2502 Part 1:1963 (Legacy BBS)
Historical bar-bending schedule conventions. Superseded by IS 2502:1969; included for archival project reference.
| Reference | Value | Clause |
|---|
| Code status | Earlier (1963) part — superseded substantively by IS 2502:1969 | Foreword |
| Application | Bar bending and fixing — drawing notation | Cl. 1 |
| Standard hook — 180° (U-hook) | 9 d total (4 d tail + half-circle) | Cl. 4 / Fig. 1 |
| Standard hook — 90° L-bend | 4 d straight tail beyond bend | Cl. 4 / Fig. 1 |
| Mandrel — plain bars ≤ 25 mm | 2 d (Fe250) | Cl. 5 |
| Mandrel — plain bars > 25 mm | 3 d (Fe250) | Cl. 5 |
| Bend allowance — 90° | Deduct ≈ 2 d from straight length | Annex |
| Bend allowance — 45° | Deduct ≈ 0.4 d | Annex |
| Cutting length | Centreline length ± allowances per bend angle | Cl. 6 |
| Stirrup hook — angle for plain bar | 135° preferred (now 135° mandatory for seismic) | Cl. 4 |
| Standard shape codes | Drawing convention defined | Annex |
| Tolerance — cut length (typical) | ± 25 mm on bar of length ≤ 12 m | Cl. 7 |
| Use today | Largely historical reference; use IS 2502:1969 for live work | Foreword |
⚠ Many provisions overlapped with later 1969 publication. Most projects today cite IS 2502:1969 + IS 1786/IS 13920 jointly.
Overview
- Status
- Current
- Usage level
- Frequently Used
- Domain
- Structural Engineering — Tunneling and Underground Structures
- Type
- Code of Practice
Also on InfraLens for IS 2502
BIM-relevant code. See the BIM Hub for ISO 19650, IFC, and LOD/LOIN frameworks used alongside it.
Practical Notes
! Always account for bend elongations (deductions) when calculating cut lengths to prevent the fabricated bars from being oversized.
! Use the correct mandrel diameter during bending to avoid micro-cracking at the bends, especially for HYSD and TMT bars.
! BBS detailers must follow these standard dimensions unless overridden by specific seismic detailing requirements (like IS 13920).
Frequently referenced clauses
reinforcement steelmild steelHYSD barsconcrete
International Equivalents
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International Comparison — Coming Soon
We're adding equivalent international standards for this code.
Key Values6
Quick Reference Values
standard u hook allowance9d (per hook)
standard 90 degree bend allowance5d
cutting length tolerance± 25 mm
bending dimension tolerance± 10 mm
minimum internal radius mild steel2d
minimum internal radius hysd bars4d
Key Formulas
Cut Length of Bar with 2 U-Hooks = L + 18d (where L is straight length and d is bar diameter)
Tables & Referenced Sections
Key Tables
Table 1 - Standard Hooks and Bends
Table 2 - Dimensions for Stirrups and Ties
Table 3 - Bending Dimensions for Binders and Links
Key Clauses
Clause 3 - Measurement of Bending Dimensions
Clause 4 - Dimensions of Hooks and Bends
Clause 6 - Tolerances on Cutting and Bending
Clause 7 - Bending and Fixing of Bars
Frequently Asked Questions3
What is the standard allowance for a U-hook?+
The standard hook allowance is 9 times the diameter of the bar (9d) per hook.
What is the permissible tolerance for the cut length of a reinforcement bar?+
The permissible cutting tolerance is ± 25 mm as per Clause 6.
What is the standard allowance for a 90-degree bend?+
The standard allowance to be added for a 90-degree bend is 5 times the bar diameter (5d).