The size of a plinth beam for a 2, 3, or 4 storey house depends on various factors, including the structural load and design specifications, the type of soil, building materials, and local building codes to determine the appropriate size for the plinth beam.

When we go through the plinth beam 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) plinth beam 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 beam, 4) large span greatly influence the bending moment on beam, 5) Thumb Rule for plinth beam design are appropriate for very small project like G+1,G+2 & G+3 Building and 6) plinth beam design for building construction it depend on many factors like topography, whether and size of building.

**◆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**

In this article, we will go through the essential thumb rules to be followed for giving a plinth beam layout. Ofcourse plinth beam 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 plinth beam to be followed are as follows:1) height of structure, 2) clear span between column, 3)Alignment of columns and various load applied on it.

The size of the plinth beam depends on the total load on the beam. 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.

**What is the plinth beam size for 2, 3 and 4 storey house?**

Usually width of the beam is kept as 9″ or 225mm because, the width of wall is 9″ in India. So that the appearance of the structure will be good.

The minimum size of an RCC Plinth beam should not be **smaller** than **9″** x **9″** (or 225 x 225 mm). **Typically,** **the** Plinth beam size for **a** **one-story** (G+0) building is **9** **×** **9** inches (or 225 × 225 mm), and for **a** **two-story** (G+1), **three-story** (G+2) and **4-story** **(G+3),** **the** Plinth beam size **of** **the** **house** is 9 × 12 inches (or 225 × 300 mm).

The standard size of a typical Plinth beam for a normal house is 12 inches deep and 9 inches wide, which means 9 × 12 inches, in feet it is 0.75 × 1 feet, in mm it is 230 × 300 mm, in cm it is 23 × 30 cm, and in meters it is 0.23 × 0.3 meters.

**Plinth beam depth**:- In genral practices, for a normal house, the depth of a typical Plinth beam is range from 9 inches to 12 inches (or 0.75 to 1 feet) deep. Generally, the depth of the Plinth beam is 9 inches deep for a one story house (G+0) and 12 inches deep for a two story house (G+1).

**Minimum size of plinth beam**

The minimum size of an RCC plinth beam should not be less than 9”x 9” (225mm x 225mm) with 4 bars of 12mm Fe500 Steel with m20 grade of concrete, stirrups of T8@6″C/C is applicable and providing clear cover of 25mm.

**Plinth beam size for 1 storey (G+0) house**

As a general thumb rule, the typical Plinth beam size for a one storey (G+0) home is 9 × 9 inches (or 0.75 × 0.75 feet, or 230 × 230 mm). The standard Plinth beam size for a one storey (G+0) house is 9 inches deep and 9 inches wide.

For a one storey (G+0) house or in simple ground floor/1st floor building, general thumb rule, using standard 5″ walls, size of Plinth beam should be 9”x 9” (230mm x 230mm) provided with 2 nos of 10mm bar at top and 2 nos of 12mm bar at bottom of Fe500 Steel with m20 grade of concrete and stirrups of T6@6″C/C.

**Plinth beam size for 2 storey (G+1) house**

As a general thumb rule, the typical Plinth beam size for a two storey (G+1) home is 9 × 12 inches (or 0.75 × 1 feet, or 230 × 300 mm). The standard Plinth beam size for a 2 storey (G+0) house is 12 inches deep and 9 inches wide.

For a 2 storey (G+1) house or in simple 2 floor building, general thumb rule, using standard 9″ thick walls, size of Plinth beam should be 9”x 12” (230mm x 300mm) provided with 2 nos of 12mm bar at top, 2 nos of 12mm bar at bottom and 1 extra bar of 10mm is provided in mid span of bottom and near both column support end in top of Fe500 Steel with m20 grade of concrete and stirrups of T8@6″C/C.

**Plinth beam size for 3 storey (G+2) house**

As a general thumb rule, the typical Plinth beam size for a three storey (G+2) home is 9 × 12 inches (or 0.75 × 1 feet, or 230 × 300 mm). The standard Plinth beam size for a 3 storey (G+0) house is 12 inches deep and 9 inches wide.

For a 3 storey (G+2) house or in simple 3 floor building, general thumb rule, using standard 9″ thick walls, size of Plinth beam should be 9”x 12” (230mm x 300mm) provided with 2 nos of 12mm bar at top, 3 nos of 12mm bar at bottom of Fe500 Steel with m20 grade of concrete and stirrups of T8@6″C/C.

**Plinth beam size for 4 storey (G+3) house**

As a general thumb rule, the typical Plinth beam size for a four storey (G+3) home is 9 × 12 inches (or 0.75 × 1 feet, or 230 × 300 mm). The standard Plinth beam size for a 4 storey (G+0) house is 12 inches deep and 9 inches wide.

For a 4 storey (G+3) house or in simple 4 floor building, general thumb rule, using standard 9″ thick walls, size of Plinth beam should be 9”x 12” (230mm x 300mm) provided with 2 nos of 16mm bar at top, 2 nos of 16mm bar at bottom and 2 extra bar of 12mm is provided in mid span of bottom and near both column support end in top of Fe500 Steel with m20 grade of concrete and stirrups of T10@6″C/C.

**Conclusions:-**

The standard size of a typical Plinth beam for a normal house is 12 inches deep and 9 inches wide, which means 9 × 12 inches, in feet it is 0.75 × 1 feet, in mm it is 230 × 300 mm, in cm it is 23 × 30 cm, and in meters it is 0.23 × 0.3 meters.