With most things in life, foundation is everything. Whether you are building a 3-layered cake, starting a new business or training a new puppy, your foundation matters. If you want something to last you have to have a solid foundation. Otherwise get ready for the mess you’ll have to clean up or the things you’ll have to fix.
The same is true when constructing a new parking lot or driveway. A solid foundation will be a big factor in how long your parking lot or driveway lasts. Without a solid foundation, cracks and potholes become a problem a lot quicker. Without a solid foundation, the pavement won’t be able to handle the weight of what it will be required to.
When having concrete or asphalt paved there are 2 terms you should know in reference to the foundation: subgrade and subbase.
When contractors refer to the subgrade they are talking about the bottom layer which is the native soil on which everything is built off of. It is also sometimes called the formation level. The subgrade needs to be compacted tight. If it is not compacted tight then certain areas can later be depressed causing an uneven subgrade.
The second layer is known as the subbase. The subbase is usually made up of aggregates including recycled concrete, stone or crushed bricks. The subbase is what ensures that the pavement can carry the weight it is supposed to. It helps to evenly distribute the weight, not putting too much pressure on one area. It also helps with drainage and protection from frost. In addition, the subbase helps the workers from dealing with mud if it rains during construction. The important aspect of the subbase is that it is uniform across the base.
It is important to work with a contractor who will build a solid foundation for your pavement. Often times contractors will cut costs on the subbase in order to provide you with a cheaper estimate, but it will cause you more troubles in the long run. If you are getting the work done it is best to get it done right.