No matter what project building construction professionals are working on, the foundation of the building is important in construction. A foundation in construction is the load-bearing part of a building whether it’s residential or commercial. This structural element connects the building with the ground level.
Despite the availability of different types of foundations, choosing the right one for your building can be difficult. The choice of building foundation is important because it determines the durability of a building. Residential or commercial construction companies can help you to make the right choice.
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Why Choosing the Right Building Foundation Matters in Construction?
After answering what is foundation in construction, let’s talk about why is the selection of the right foundation important.
Well, here are some major benefits of choosing the right type of foundation in construction.
- Building foundations bear all the load ranging from the constant weight of the building structure to the variable weight of objects and living beings
- Furthermore, a strong foundation enables the building to withstand extreme weather conditions such as storms, floods, etc.
- A strong foundation also provides adequate insulation to your building.
- In the end, a building foundation is crucial for the overall stability and functionality of a building.
Let’s dive deeper into the details and find out about the different types of building foundations in construction.
Types of Foundations in Construction
Whether you are going to choose a foundation for your residential or commercial buildings, knowing about your options is important. There are a variety of factors to consider while choosing a building foundation such as local weather conditions, the nature of the soil, etc. Also, selection of building materials for foundation is also an important consideration.
The following are the two types of building foundations:
1- Shallow Foundation
2- Deep Foundation
Shallow foundations are also known as open or spread footing. These types of foundations in construction are recognized for their width which is more than their depth. Being a perfect choice for smaller and lighter buildings, shallow foundations are chapter and faster to build. These building foundations can be chosen for residential buildings.
Normally, the depth of these foundations is less than 6 feet and they have sufficient weight-bearing capacity. The shallow foundations in construction have many further sub-types. These include:
Individual Footing/ Isolated Footing
This is one of the most common types of shallow building foundations. This type of foundation is preferred in buildings where the overall building load is supported by the columns. For supporting these columns, individual footing is preferred.
Individual footing looks like a piece of concrete in a square or rectangular shape on which the column sits. These individual footings are then connected to each other using a beam that rests at the ground level. The overall size of individual footing is calculated according to the load-bearing capacity of soil and the overall load on the machine.
Just as the name indicated, these combined footings are formed by connecting many individual footings. Combined footings are placed at the positions when multiple columns are placed together and their individual footings start overlapping.
This type of foundation supports the overall weight of adjacent columns and distributes weight to a wider soil area. These footings are rectangular in shape despite the fact they all look like they may have different structures. Combined footings are often used in the construction of buildings in areas where soil weight-bearing capacity is limited.
Strip foundation also known as strip footing is a type of shallow foundation that usually supports load-bearing walls. This uses a stripe of concrete that is present beneath the weight-bearing walls. The positioning and size of this concrete strip may vary depending on the required width.
This foundation is preferable for places where the soil has good weight-bearing capacity. The working principle behind strip foundations is that at 45 degrees, the load is transferred from the wall to the soil. Strip foundation is the perfect choice for low-to-medium rise building so these can be a great choice as an ideal foundation type for home.
Raft or Mat Foundation
Another type of shallow foundation is the raft or mat foundation. Being a shallow foundation, there is no need for deeper excavation of the ground. Unlike isolated footings, the raft of mat foundation is a continuous slab that runs through the entire building footprint.
This type of foundation is capable of supporting heavy loads from columns and walls. Moreover, in buildings where chances of damage to individual footing are high due to heavy structural weight, raft foundations are preferred. Soil with low-bearing capacity is also good for this type of foundation. However, this foundation type isn’t suitable for the places where groundwater level is above the soil-bearing surface.
Unlike shallow foundations, another type of foundation is the deep foundation. This type of foundation is preferable for heavy buildings such as skyscrapers or plazas. Also, this type of foundation can support the structures in water environments and are also used in building and dams.
The primary requirement for deeper and stronger foundations makes deep foundations ideal for these buildings. The weight-bearing capacity of deep foundations is significantly more than that of shallow foundations.
Deep foundations are not really for residential buildings. This foundation type provides support and stability which is not provided by soft or weak soil. The taller a building is the deeper the foundation it requires. Deeper foundations can be of the following sub-types.
Pile foundations are a type of deep foundation that is made up of concrete (reinforced) or steel that is inserted deeply to create a strong base. These concrete or steel long and thin elements transfer the weight to the sturdy base to provide support.
To use the pile foundation, the solid surface should be weak with high levels of underground water, hard-to-excavate soil, and a deep drainage system. This appears as long and cylindrical columns and is often used to build structures near water bodies. Pile foundation has the following subtypes:
- Sheet piles (present in the form of sheet, these pile foundations are responsible for the lateral support).
- End-bearing piles (these piles transfer weight from thin elements to a stringer layer of soil or rock).
- Friction piles (These piles use the friction between the [ile surface and soil around it to transfer weight on the lower-lying surface).
- Load bearing piles (Load bearing piles are responsible for transferring load from vertical structure to soil)
- Soil connector piles (These pile foundations don’t bear any weight but indirectly help to increase the load-bearing capacity of the soil).
Drilled shafts also known as caissons are another type of deeper foundation. These foundations consist of the log and cylindrical columns that are mainly responsible for providing stability underwater. This makes them an ideal choice for dams, bridges, hillside residential properties, etc.
These drilled shafts are usually built near or at the ground surface initially and later sunken to the desired depth. These shafts are usually drilled in the soil layers below the water surface. These caissons can be of different types such as:
- Open (Comes with an open top and bottom)
- Box (closed at the bottom and open at the top)
- Sump (Comes with the ability to pump water from beneath)
- Pneumatic (Have a pressurized chamber where soil or mud can’t enter).
Choose the Best Building Foundation Type
The choice of foundation for your residential or commercial building can be a tough decision to make. Each foundation type has its own pros and cons. However, your decision for the best foundation can vary depending on a lot of factors including your house location, weather conditions in the area, budget, and much more. This is why it is best to leave the decision to the professional constructor.