How do I know what size footing I need?

How to Calculate Footing Size

1. Determine the width and length of the cement slab in inches.
2. Divide the width by 12 to convert it to feet.
3. Divide the length by 12 to convert it to feet.
4. Determine the depth or thickness that is required for the footing in inches.
5. Multiply the width by the length and then by the depth.

What is the size of footing for 3 storey building?

Column footing size for 3 storey (G+2) building:- for 3 storey (G+2) house or in simple 3 floor building, general thumb rule, using standard 9″ thick walls, we recommended size of column footing should be 5’×5’×5′ (1.5m x 1.5m×1.5m) for isolated footing shallow foundation in gravel and sand soil with higher bearing …

How do I choose the right foundation for a building?

Foundation Selection Criteria for Buildings

1. Loads of Structure.
2. Soil Bearing Capacity.
3. Soil Types.
4. Ease of Construction.
5. Water Table Level.
6. Adjoining Structure/Water Bodies/Slopes.
7. Natural Disaster and Extreme Weather.
8. Economic Design.

How deep should a footing be?

Depth of Footings Footings should extend to a minimum depth of 12 inches below previously undisturbed soil. Footings also must extend at least 12 inches below the frost line (the depth to which the ground freezes in winter) or must be frost-protected.

What are the factors to be considered in choosing the type of footing to be used in a certain building?

The selection of a particular type of foundation is often based on a number of factors, such as:

• Adequate depth.
• Bearing capacity failure.
• Settlement.
• Quality.
• Adequate strength.
• Adverse soil changes.
• Seismic forces.

What is the best soil type for foundations?

Loam
Loam is a good soil for supporting a foundation, as long as no miscellaneous soils find their way onto the surface. Rock – Types such as bedrock, limestone, sandstone, shale and hard chalk have high bearing capacities. These are very strong and good for supporting foundations because of their stability and depth.