**Footing depth & size** is very important for every building. Because all building load comes on footing by the help of columns. So **footing depth & size** should be of standard size. Generally footing depth and size is decided by thumb rule up to the 5 storey building, and after 5 storey building it is decided by the more factor like types of building, load of building, etc. Therefore we are going to discuss **footing depth & size for 1, 2, 3, 4, and 5 storey house**s.

The depth and size of the footing depend upon various factors. Like Types of soil, bearing capacity of the soil, and live and dead load that will come on footing. Footing depth and size are more important for commercial buildings. Because commercial building carries more load compared to residential buildings.

**For the Footing depth and size of residential houses, some general thumb rule has been followed.**

## What is footing

Footing is part of the foundation of a building and it is the deepest part of the building. This is that part of the building which directly in contact with the soil, and it supports all structure load. The footing is the deepest part of the foundation, and it is made up of concrete. Therefore standard size and depth of footing are very important for any structure.

### Footing Depth and size for 1 storey house

According to the Thumb rule the **depth of footing for a single-storey house** should not be less than 3 feet. And the size of footing for single-storey buildings also should not be less than 3 feet. But I suggest that you should keep your **footing depth** 3.5 feet (1m) and you should keep your footing size for single-storey buildings 3.5 × 3.5 feet (1m × 1m). M20 grade concrete use in the footing always, and a minimum of 40mm (1.5″) of concrete cover should be in the footing.

**Reinforcement Details in Footing**

Steel bars that use in the footing Should be always a minimum Fe 500 grade. The steel bar’s size should not be less than 10mm for the footing of single-storey building. But I suggest, you use 12mm of steel bars at 6 inches of c/c spacing in the footing for single-storey buildings.

### Footing Depth and size for (G+1) 2 storey house

According to the Thumb rule the **depth of footing for 2 storey house** should not be less than 4 feet, and the size of footing for 2-storey buildings should be 3.5 × 4.5 feet. But I suggest that you should keep your footing depth 4.5 feet and you should keep your footing size for 2-storey buildings 4’× 4′. M20 grade concrete use in the footing always, and a minimum 40mm (1.5″) of concrete cover should be in the footing.

**Reinforcement Details in Footing**

Steel bars that use in the footing Should be always a minimum Fe 500 grade. The steel bar’s size should not be less than 10mm for the footing of 2 storey building. But I suggest you use 12mm of steel bars at 6 inches of c/c in the footing for 2 storey building.

### Footing Depth and size for (G+2) 3 storey house

According to the Thumb rule the **depth of footing for 3 storey house** should not be less than 4 feet, and the size of the footing for 2-storey buildings should be 5 × 5 feet. But I suggest that you should keep your footing depth 5.5 feet, and you should keep your footing size for 3-storey buildings 5′ × 4′. M20 grade concrete use in the footing always, and a minimum 40mm (1.5″) of concrete cover should be in the footing.

**Reinforcement Details in Footing**

Steel bars that use in the footing Should be always a minimum Fe 500 grade. The steel bar’s size should not be less than 10mm for the footing of 3 storey building. But I suggest you use 12mm of steel bars at 6 inches of c/c spacing in the footing for 3 storey building.

### Footing Depth and size for (G+3) 4 storey building

According to the Thumb rule the **depth of footing for 4 storey building** should not be less than 6 feet, and the size of the footing for 4-storey buildings should be 5 × 5 feet. But I suggest that you should keep your footing depth 6.5 feet, and you should keep your footing size for 2-storey buildings 5′ × 6′. M20 grade concrete use in the footing always, and a minimum 40mm (1.5″) of concrete cover should be in the footing.

**Reinforcement Details in Footing**

Steel bars that use in the footing Should be always a minimum Fe 500 grade. The steel bar’s size should not be less than 12mm for the footing of 4 storey building. But I suggest you use 16mm of steel bars at 6 inches of centre-to-centre spacing in the footing for 4 storey building. If you want to use 12mm steel bar then you will keep the c/c spacing of 5 inches.

### Footing Depth and size for (G+4) 5 storey house

According to the Thumb rule the **depth of footing for 4 storey house** should not be less than 7 feet, and the size of footing for 5-storey buildings should be 6 × 6 feet. But I suggest that you should keep your footing depth 7.5 feet, and you should keep your footing size for 2-storey buildings 7′ × 7′. M20 grade concrete use in the footing always, and a minimum 40mm (1.5″) of concrete cover should be in the footing.

**Reinforcement Details in Footing**

Steel bars that use in the footing Should be always a minimum Fe 500 grade. The steel bar’s size should not be less than 12mm for the footing of 5 storey building. But I suggest, you should use 16mm of steel bars at 6 inches of c/c spacing in the footing for 5 storey building.

### Some important points to keep in mind during Footing.

- All the above information related to the depth and size of the footings should be applied when the soil condition is good. If your soil condition is not good then you should consult a structural engineer.
- It is recommended to go to the depth up to the hard strata.
- The best footing for the house is isolated footing instead of spare or rectangular footing. Because isolated footing can bear more load than spare or rectangular footing.
- You should do 4 inches thick PCC before placement of the mesh net, and do not put the mesh net on the soil.
- Footing thickness should not be less than 8 inches.

**You Should Also Read:**

**How much Cement, Sand, and aggregate required for 1m3 M10 grade concrete****RCC cost per cubic feet/ per sq ft/ per cubic meter**

#### Conclusion

Guys, In this article we have known what is the right **size of footing for 1, 2, 3, 4, and 5-storey houses**. We also know what is the **standard depth of footing for 1, 2, 3, 4, and 5-storey houses**.

##### FAQ

**How deep should a foundation be for a 3-storey building?**

The depth of the foundation should be 5.5 feet, and the size of the foundation should be 5′ × 4′ (Length × width) for 3 storey building.

**What is the standard depth of footing?**

The standard depth of footing is 5 feet or 1.5m for a residential house.

**What is the footing depth for 4 storey building?**

The depth of the footing should be 6 feet, and the size of the footing should be 6′ × 5′ (Length × width) for 4 storey building.

**What is the footing depth for 5 storey building?**

The depth of the footing should be 7 feet and the size of the footing should be 7′ × 7′ (Length × width) for 5 storey building.