Updated August 20th, 2019

An RCC column has two types of bar. One is the **longitudinal bar** and another is the **horizontal bar**.

As the horizontal bar, we use stirrups and ties. Stirrup also has some other names in the construction sector. Such as Ring, Shear reinforcement, etc.

For making column stirrups, you have to calculate the cutting length of a bar and the number of required stirrups and then determine the size of the stirrup.

You can do this in four easy steps.

## 4 Easy Steps for Making Column Stirrups

Making column’s stirrup involves the following 4 steps of work.

- Determining the size of stirrups
- Calculating the cutting length of a bar
- Calculating the number of stirrups
- Bending the bar in stirrup’s shape

### 1. Determine The Size of Stirrup

See the above image. The column size is **20″ × 40″** and the concrete clear cover for reinforcement is **1½”**.

So the length of stirrup will be,

= Long side of column – 2 × clear cover

=40″-2 × 1½”

=**37″**.

And the width will be,

= The short side of the column – 2 × clear cover

=20″-2 × 1½”

=**17″**.

So the size of a stirrup is **37″ × 17″**.

### 2. Calculating Cutting-Bar-Length for Stirrup

Before cutting the bar you have to calculate the **cutting bar length** for the stirrup.

There are two terms – the **Actual bar length** and the **Cutting bar length**.

**The actual bar length of a stirrup** is,

=2 × length + 2 × width + 2 × hook’s length

= 2 × 37″ + 2 × 17″ + 2 × 3″

= **114″ or 9½** feet.

Let’s discuss a little about hook’s length.

The hook length is calculated by a formula that is **6db** (*db=diameter of the stirrup bar*).

So the hook length for **10mmø **bar is,

= 6 × 10

= 60 mm.

But the length of a hook should not be less than **75mm **(*as per code*).

So the hook length for the stirrup is **3″** (75mm = 3″).

The **actual bar length** of the stirrup is **9½** feet.

But the **cutting bar length** will be less than the **actual bar length**.

See the above image. That is our stirrup.

The stirrup has three numbers of **90°** bend and two numbers of **135°** hook.

For each bend, the length of the bar will be reduced.

There is a certain formula to calculate the reduced length for a bend.

The formula needs various calculation process. I’ll write about the formula some other day in this blog.

Below I’m giving a chart for the reduced length of a 90° bend for different size of bars.

*10 mmø bar – 1″**12 mmø bar – 1¼”**16 mmø bar – 1½”*

Since, we are using **10 mmø** bar for our stirrups so the **cutting bar length** will be,

=9½’ – (3 × 1″) (*bend deduction is ignored for 135° bend*).

= **9′-3″**

So, you have to cut **9′-3″** length of **10mmø **bar.

That means, **cutting bar length** for the stirrup is **9′-3″**.

** Read More:** How To Calculate The Cutting Length Of Various Shaped Stirrups?

### 3. Calculating The Number of Stirrups

In the image above, there are two types of spacing for stirrups. One is **S1 **and another is **S2**. S1 is spaced **4″ c/c** and S2 is spaced **8″ c/c**.

S1 is provided in the bottom ¼th portion and the top ¼th portion of clear column’s height.

S2 is provided in the middle half portion of the clear column’s height.

The clear column’s height means the height of a column between the top of the floor to the bottom of the roof-beam.

You also should provide 2 numbers of stirrups into beam-column joint.

Now let’s calculate the numbers of required stirrups for the column.

The floor height is 10 feet.

The roof-beam height is 2 feet.

So the Clear height of the column is,

= floor height – beam height

= 10′ – 2′

=8 feet.

The required number of stirrups are,

= (4’÷4″) + (4’÷8″) + 2 + 1 (*1 bar should be added for getting the correct number of stirrups*).

= **21 nos**.

### 4. Bending The Bar in Stirrup’s Shape

You can use stirrup-making-machine for a large project where a vast quantity of stirrups is required.

But, we often make stirrups manually in our project.

For making stirrups by hand you need a *stand* and a *handle*.

See the above image. That is a hand-made stand and a handle. You can make stirrup with these tools.

Just place the rod in the stand and bend the rod with the handle. You have to go for trial and error method to get the desired size of a stirrup. Also, don’t forget to make the hook angle at **135°**.

**Symbols used in this post:**

**“**– inch**‘**– foot**°**– degree**db**– diameter of the bar**nos**– numbers**ø**– diameter**c/c**– center to center distance

*Your Turn*

*How do you make stirrup bending stand? How do you make the handle? How do you calculate the deduction length for the bend of different size bars?* *Please share in the comments below…*

**Editor’s Note:** This post was originally published in May 2017 and has been completely revamped and updated for accuracy and comprehensiveness.

tofayel ahammed says

Please explain this……..

Number of stirrups are,

= 4'/4" + 4'/4" + 2 + 1 (1 bar should be added for getting the correct number of stirrups.)

= 27 nos.

Ali says

Bro this works like that. The total height of column is 8′ and We have two types of Stirrups. S1 and S2. S1 is placed at 2′ at top and 2′ at bottom and S2 acts in the middle (remaining height) 4′ so its 4′ (total height where S1 is used 2 top + 2 bottom)/4″” + 4’/8″ +2 + 1

Hope this helps

Sunil Chaudhary says

why 2 is added while calculating no of stirrups??

Liton Biswas says

This is required practically.

Rana says

Why s1 s2. Why no s3 also

mohd naved says

what length will we reduce for 8 mm and 6 mm rings to calculate exact length of stirrup

Ajay says

8mm dia dimensions is 100+185+100=385-32bend deduction=353 total length is it correct. Shape is hook

Mulugeta kefelegn ,Demissie says

Good idea

Liton Biswas says

Thanks, Mulugeta.

raja says

why the No of stirrups is difference in top, bottom, & middle section? if I set up or calculated all C/C distance are same, is it wrong??? but why?

Liton Biswas says

Hi Raja,

This is a structural design related issue. More share forces are involved in the top and the bottom portion of the column. That’s why stirrups spacing is less.

Babu says

Please explain how we determine nos of stirrups (if we havr one type of stirrups)

Sk. Abed Ali says

How we can calculate the bar deduction bending hooks in stirrup for 8mm?

Peddaiah says

Thanks for clarified doubts. These are very useful for learners

Jessie says

In my own analysis, the 10cm distance spacing of stirrups or less 10cm distance spacing of stirrups are best, because the more stirrups we use, the better and stronger the beam or column will become.