**What is the column size for 2, 3 and 4 storey building?** Hi guys in this article we know about column size for 2 storey 3 storey and 4 storey building & minimum size of RCC column according to IS code 456.

**◆You Can Follow me on Facebook and Subscribe our Youtube Channel**

**You should also visits:-**

**1)what is concrete and its types and properties**

**2) concrete quantity calculation for staircase and its formula**

**When we go through the column design we should mention following point**: 1) the possible distance or span and depth it all depend on load to which the beam is subjected, 2) column size depend on amount of load on the column acting on it by beam and RCC slab, 3) many axial and Lateral load acting on column, 4) large span greatly influence the bending moment not only on beam, but it also affect the column due to stress acting on it, 5) Thumb Rule for column design are appropriate for very small project like G+1,G+2 & G+3 Building and 6) column design for building construction it depend on many factors like topography, whether and size of building.

In this article, we will go through the essential **thumb rules** to be followed for giving a column layout. Ofcourse columns have to be designed in accordance to the total forces acting on the structure, but apart from that, it is essential for every Civil engineer and Architect to remember a few thumb rules so that they are prevented from making mistakes.

Three thumb rules for design of column to be followed are as follows:1)Size of the Columns, 2)Distance between Columns & 3)Alignment of columns.

**The size of the columns depends on the total load on the columns**. There are axial loads and lateral loads. Large beam spans induce bending moment not only in the beams, but also in columns which are pulled by the stresses in the beams.

**Minimum size of RCC column:**-minimum size of an RCC column should not be less than 9”x 9” (225mm x 225mm) with 4 bars of 12mm Fe500 Steel with m20 grade of concrete and stirrups of [email protected]″C/C.

**Column size for ground floor/1st floor building:-** For this general thumb rule, we will assume a structure of ground/1st floor building, using standard 5″ walls, size of an RCC column should be 9”x 9” (230mm x 230mm) with 4 bars of 12mm Fe500 Steel with m20 grade of concrete and stirrups of [email protected]″C/C.

**Column size for 2 storey (G+1) building:-** For this general thumb rule, we will assume a structure of G+1 (2 storey) building, using standard 5″ walls, size of an RCC column should be 9”x 12” (230mm x 300mm) with 6 bars of 12mm Fe500 Steel with m20 grade of concrete and stirrups of [email protected]″C/C.

**Column size for 3 storey (G+2) building:-** For this general thumb rule, we will assume a structure of G+2(3 storey) building, using standard 5″ walls, size of an RCC column should be 12”x 12” (300mm x 300mm) with 6 bars of 12mm Fe500 Steel with m20 grade of concrete and stirrups of [email protected]″C/C.

**Column size for 4 storey (G+3) building:-** For this general thumb rule, we will assume a structure of G+3/4 storey building, using standard 5″ walls, size of an RCC column should be 12”x 14” (300mm x 350mm) with 4 bars of 16mm and 2 bars of 12mm Fe500 Steel with m25 grade of concrete and stirrups of [email protected]″C/C.

These days the minimum I use in my projects is 9″ x 12″ (225 mm x 300mm) with 6 bars of 12 MM Fe500 steel. You can never go wrong with strong columns. I also recommend use of M20 grade concrete for the structure (ratio 1 part Cement : 1.5 parts Sand : 3 parts Aggregate with 0.5 parts water by volume). I recommend use of 8 MM stirrups at a distance of 150 MM center to center throughout the length of column.

This setup of 9″ x 12″ RCC columns is safe for G+1 Floors. There are a lot of other considerations, but this is just a thumb rule.