A foundation is the lowest part of the building that is in direct contact with the soil upon which a building rest. Its core purpose is to transfer loads from the structure and anchor a building safely to the ground. The main pillars and columns in a building are connected to the foundation structure of a building so as to support its weight throughout its lifetime. Whether it’s a commercial or residential structure, the foundation is the most important part in construction. In the wrath of natural phenomena such as earthquakes and tornadoes, a properly built foundation will hold the structure upright ensuring safety for the people inside. A poorly constructed foundation, on the other hand, compromises the structural integrity of the entire construction.
As a homeowner, real estate agent, or landlord, knowing the different types of foundations gives you a better understanding why an architect designed the building in the manner they did. Again, for the sake of accountability of the final soundness of the building, it’s only good you know what type of foundation is expected where and when. Learn about the two categories of foundation from experienced excavation companies Scranton.
Foundations are generally categorized into two; shallow and deep foundations. Shallow foundations are also known as spread footings. These are generally made in depths of about 3 – 50ft. Shallow foundations are only suitable for small and light buildings, such as two-story buildings. While making shallow foundations, all the earth in the designated construction area is excavated until the required depth. The footing of the construction, which is made of concrete, is then set up at the very bottom of the excavated land. Such footing is meant to support the weight of every column in the building and spread its load over a larger surface area. As a result, the building remains firmly anchored to the ground.
Footings are part and parcel of shallow foundations. Soil weakens as it nears the ground level. The shallow depth of the foundation may therefore not reach the strong rock bed found deep underground. Footings ensure that the weight of the building is spread out enough to maintain the safe bearing capacity of the soil above the rock bed. Deep foundations, on the other hand, are made at a depth of about 60 – 200ft. They can run deep enough to reach the firm bedrock, which allows the construction of taller, heavier buildings such as towers and skyscrapers.
Unlike shallow foundations which rely on footing, deep foundations make use of piles. Piles are strong cylindrical structures made of concrete which are pushed deep into the excavated earth to make them sturdy enough to support structures built on top. Piles are necessary when the layer of soil just above the ground is too weak to support such a heavy building. The piles bypass this load to the more stable bedrock deep underground. They make a more robust support structure as compared to footings.
Both deep and shallow foundations need to be re-filled with the excavated soil, a process known as backfilling. This is done by re-filling the soil back one foot-thick at a time and compressing it under wet, high pressure. The pressure rids the backfilled soil off any air voids, ensuring the safe bearing capacity of the soil just below the floor slab at ground level.
Foundation problems are both very time consuming and costly to repair. Yet, if left unaddressed, minor foundation problems only get bigger and more expensive. But, how about you prevent the need foundation repairs by hiring building contractors who do it right from the very onset.