According to the **IS-456:2000**, the minimum spacing between the individual reinforcement bars is determined as follows.

**A. Minimum horizontal spacing:**

As per IS-456:2000, the **minimum horizontal distance** between the individual bars shall be the maximum of the following three conditions.

**1. Equal diameter bars:**

**20mm.**

**2. Unequal diameter bars:**

**25mm.**

**3. Aggregate size:**

Suppose if we use a coarse aggregate of 20mm. size, the minimum spacing as per condition - 3 is

= [nominal size of coarse aggregate + 5mm.]

= [20mm. + 5mm.] = **25mm.**

Here, the maximum value in all three conditions is **25mm.**

So, we have to consider **25mm. **as the minimum horizontal spacing.

If we use a coarse aggregate of 25mm. size., the minimum spacing will be

= [25mm.+ 5mm.] = **30mm.**

Here, we have to consider **30mm**. (greater value) as the minimum horizontal spacing.

**B. Minimum vertical spacing:**

As per IS-456:2000, the minimum vertical distance between the individual bars shall be the maximum of the following three conditions.

**1. Minimum requirement:**

In any situation ( condition-1), the minimum vertical bar spacing shall not be less than **15mm.**

If the diameter of the bars is ≤12mm., the minimum vertical distance shall be 15mm. In this case, we cannot consider 12mm. ( bar dia.) as the minimum spacing.

**2. Aggregate size:**

Suppose we use a coarse aggregate of 20mm. size, the minimum vertical spacing as per condition - 2 is

= [ 2/3 × nominal size of coarse aggregate ]

= [2/3 × 20mm.] = **13.33mm.**

**3. Bar diameter:**

**20mm.**

**20mm.**

Here, we have to consider **20mm**. as the minimum vertical spacing.

**Note:**

1. Whatever might be the permutation & combination of conditions, in all cases you have to choose the greater value as a minimum spacing.

2. Minimum spacing is the clear span ( not c/c distance) between the individual bars.

**Thank you for going through this article❤. Have a good day ðŸ˜„.**

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