Bending of stainless steel reinforcing bar is covered by BS8666:2020.

Below shows the shapes and formula covered in the current standard. Previous standard can be found here.

Download leaflet with BS8666 2020 bending details.

Shape Code 00

Shape Code 01

Shape Code 11
BS8666 Shape Code 00 BS8666 Shape Code 01 BS8666 Shape Code 11
Length = A (Cut to Length) Length = A (stock lengths) Length = A + (B) – 0.5r – d

Shape Code 12

Shape Code 13

Shape Code 14
BS8666 Shape Code 12 BS8666 Shape Code 13 BS8666 Shape Code 14
Length = A + (B) – 0.43r -1.2d Length = A + 0.57B + (C) – 1.6d Length = A + (C)

Shape Code 15

Shape Code 21

Shape Code 22
BS8666 Shape Code 15 BS8666 Shape Code 21 BS8666 Shape Code 22
Length = A + (C) Length = A + B + (C) – r -2d Length = A + B + 0.57C + (D) – 0.5r – 2.6d

Shape Code 23

Shape Code 24

Shape Code 25
BS8666 Shape Code 23 BS8666 Shape Code 24 BS8666 Shape Code 25
Length = A + B + (C) – r – 2d Length = A + B + (C) Length = A + B + (E)

Shape Code 26

Shape Code 27

Shape Code 28
BS8666 Shape Code 26 BS8666 Shape Code 27 BS8666 Shape Code 28
Length = A + B + (C) Length = A + B + (C) – 0.5r – d Length = A + B + (C) – 0.5r – d

Shape Code 29

Shape Code 31

Shape Code 32
BS8666 Shape Code 29 BS8666 Shape Code 31 BS8666 Shape Code 32
Length = A + B + (C) Length = A + B + C + (D) – 1.5r – 3d Length = A + B + C + (D) – 1.5r – 3d

Shape Code 33

Shape Code 34

Shape Code 35
BS8666 Shape Code 33 BS8666 Shape Code 34 BS8666 Shape Code 35
Length = 2A + 1.7B + 2(C) – 4d Length = A + B + C + (E) – 0.5r – d Length = A + B + C + (E) – 0.5r – d

Shape Code 36

Shape Code 41

Shape Code 44
BS8666 Shape Code 36 BS8666 Shape Code 41 BS8666 Shape Code 44
Length = A + B + C + (D) – r – 2d Length = A + B + C + D + (E) – 2r – 4d Length = A + B + C + D + (E) – 2r – 4d

Shape Code 46

Shape Code 47

Shape Code 48
BS8666 Shape Code 46 BS8666 Shape Code 47 BS8666 Shape Code 48
Length = A + 2B + C + (E) Length = 2A + B + 2C + 2q – 3r – 6d Length = 2A + B + 2(C) – r – 2d

Shape Code 51

Shape Code 52

Shape Code 56
BS8666 Shape Code 51 BS8666 Shape Code 52 BS8666 Shape Code 56
Length = 2(A + B + (C)) – 2.5r – 5d Length = 2(A + B) + 2(C) – 2.5r – 5d Length = A + B + C + D + 2E – 1.5r – 3d

Shape Code 63

Shape Code 64

Shape Code 67
BS8666 Shape Code 63 BS8666 Shape Code 64 BS8666 Shape Code 67
Length =2A + 3B + 2(C)- 3r – 6d Length = A + B + C + 2D + E + (F) – 3r – 6d Length = A

Shape Code 75

Shape Code 77

Shape Code 98
BS8666 Shape Code 75 BS8666 Shape Code 77 BS8666 Shape Code 98
Length =∏ (A – d) + B + 25 Length = C ∏ (A – d)  Length = A + 2B + C + (D) – 2r – 4d

Reinforcing Bending Limitations.

For all shapes with two or more bends in the same or opposite directions (whether in the same plane or not), the overall dimension given on the schedule shall always include a minimum straight of 4d between the curved portion of the bends, as shown below.  The value of ‘x’ shall be not less than the following:

  1. 10d for bars not exceeding a nominal size of 16mm.
  2. 13d for nominal sizes greater than 16mm.

BS8666 Minimum dimensions

This translates to the following dimensions

Diameter Minimum
6 60
8 80
10 100
12 120
16 160
20 260
25 325
32 416
40 520

Reinforcement Bending Schedule Notations:

H H For diameters ≤12 mm, Grade B500A, Grade B500B or Grade B500C conforming to BS 4449:2005+A3:2016
For diameters ˃12 mm, Grade B500B or Grade B500C conforming to BS 4449:2005+A3:2016
A A Grade B500A conforming to BS 4449:2005+A3:2016
B B Grade B500B or Grade B500C conforming to BS 4449:2005+A3:2016
C C Grade B500C conforming to BS 4449:2005+A3:2016
D Smooth Plain round bar, straight shape code 00, for dowel bars only conforming to BS EN 13877-3
S S The specific grade(s) and steel designation number(s) of ribbed stainless steel conforming to
BS 6744 and BS EN 10088 shall be stated on each relevant bending
X X Reinforcement of a type not included in the above list having material properties that are
defined in the design or contract specification
NOTE 1 In the Grade description B500A, etc., “B” indicates reinforcing steel.
NOTE 2 Within the ranges given, the grade(s) supplied for notations H and B are at the supplier’s discretion.
NOTE 3 A specific grade(s) and type(s) of ribbed stainless steel conforming to BS 6744 and BS EN 10080
should be stated on each relevant bending schedule.