If you’re a new developer or building your dream home from scratch, you’ll quickly learn that the proposed building’s foundation is the most crucial aspect of the whole project. This is because a quality foundation will be designed to support the entire structure as well as distribute the building load to the ground beneath.
This not only ensures long-term structure stability, but also reduces the need and cost of long-term repairs and do-overs. The first step in designing the safest and most secure structure involves doing the soil testing Melbourne law requires. These tests will enable your geotechnical team to choose the best foundation type.
Understanding Why Your Home Needs a Foundation
No matter how big or small your new build is going to be, it’s going to need a foundation. Essentially, a foundation can be defined as the load-bearing base of the structure. This base is typically built below ground and is designed and expected to support the entire weight of your building and its contents.
Ideally, your foundation should be able to safely transfer the weight into the surrounding ground. A foundation must be able to anchor your home or building firmly to the ground. With this in mind, every homeowner and property developer should strive to add the strongest, most durable foundation to the space before any other building starts.
Knowing What Factors Influence Your Proposed Foundation
Depending on the type of soil conditions you’re dealing with, your geotechnical engineering team may elect to either opt for a choice between a deep or shallow foundation. Typically, a deep foundation is selected for spaces where the surface soils cannot accommodate the proposed load weight. Systems are put in place to transfer the building weight to the deeper, more stable lower layers of bedrock.
Shallow foundations, on the other hand, allow for a simple transfer of the structural load to a level under three meters of the main ground level. Unlike deep foundations, shallow options are wider, which allows for a better load spread across the overall bearing surface. This option is widely chosen for many residential and commercial builds.
The most common factors that will determine the type of foundation chosen are listed below:
- Soil conditions
- Anticipated load of the building
- Limitations offered by the site
- Moisture and groundwater variations
- Proposed budgets
Several Foundation Types to Choose From
The good news is that both shallow and deep foundations have different options to choose from. This means that getting the best foundation for long-term success is easier than you think. Here’s a quick look at the different types of foundations to choose from.
- Pile Foundations
Typically, pile foundations are among the more common deep foundation options. This process involves driving long, thin columns deeply into the ground. The columns used are typically made of steel, timber, or reinforced concrete. Your engineer will choose the pile type based on the overall soil profile and specific load requirements.
- Caisson Foundations
Another option best suited to create deep foundations is the caisson type. In this process, a deep hole is drilled into the ground, and reinforcement and concrete are placed into the holes to form durable, high-capacity columns.
You can typically expect to find this method being chosen for larger commercial projects where tall structures may require deeper and more stable support. Caissons are also excellent for providing support in spaces with varying soil types.
- Strip Footings
One of the more common options for a shallow foundation is the strip footing option. This method involves placing continuous strips of reinforced concrete beneath the walls where extensive load-bearing is required. Engineers commonly use this option in residential buildings to make load distribution easy, where the soil has a more stable bearing capacity.
- Pad Footings
Also more commonly known as isolated footings, this process falls into the shallow foundation category and is designed to support individual columns. These footing types are usually square, rectangular, or even square and will be placed underneath a column. This process will require consistent soil conditions and concentrated loads.
- Mat or Raft Foundations
Mat or raft foundations are large reinforced concrete slabs that are designed to provide support to the whole foundation of your build. This foundation type is typically chosen for sites that have poor soil uniformity or display low bearing capacity. Since mat foundations cover the whole foundation, they can easily support heavier buildings and, in the process, reduce the risk of differential settlement.
- Strap Footings
When you’re installing columns in your foundation, you may want to connect isolated footings. This can easily be done with a concrete beam that’s usually referred to as a strap beam. The goal is to help balance loads between the columns and is best suited for footings located near the property boundary.
Final Thoughts
Once your geotechnical team has completed the necessary soil tests and assessed the various factors that affect the choice of foundation, choosing the best type of foundation is the next step. It’s essential to choose an option that aligns with key soil characteristics as well as meets the structural requirements.
