The blacktop of your residential asphalt driveway often gets the most attention. While we will see the black layer daily, the subbase layer (also known as the subbase course) far beneath your driveway blacktop is the most important. According to Pavement Interactive, the subbase course is the layer between the base course and the subgrade (soil), and “it functions primarily as structural support, but it can also minimize the intrusion of fines from the subgrade into the pavement structure and improve drainage.”
Here’s a deeper look at the function of the subbase and why it is so vital to the longevity of your driveway.
Enhanced Soil Characteristics
A subbase is a layer added right on top of the soil. Because your driveway paving starts from the ground up, your asphalt paving contractor will go to great lengths to make sure that the layers building up to the blacktop are stable and appropriate for the characteristics of your property. The point of a subbase is to set the tone for the base course and surface course that will be added to the top of it during the paving process. Asphalt contractors will evaluate your soil for consistency and type before a subbase course is chosen. Then based on what is existing in your soil, a subbase course will be determined from a mix of materials such as crushed aggregate or specially engineered fill. The only way to control how well your paving fairs is to create a quality subbase that sets the rest of your project up for success. This is a critical step that determines the quality of your pavement for years.
Strong Foundation
By working with the exact characteristics of your soil, asphalt installers can get you a strong foundation for your residential paving. Regardless of compaction at the top, the strength of your driveway starts at the subbase. If your driveway doesn’t have a solid foundation, it won’t last long in the New England climate. Shifts in your pavement often happen at the subbase when it isn’t installed correctly. They are more likely to occur in our area because of the fluctuations of temperature and the intense freeze and thaw cycle that we see in Massachusetts and the surrounding areas. You should take special care when constructing the subbase to avoid premature cracks and asphalt potholes.
Expert Evaluation Matters
It could be a bad sign if an asphalt paving and repair company offers to do the driveway project without adding a subbase. While it is true that some areas don’t require it, most residential paving projects do much better over time when you add a subbase since you cannot control what construction will happen around your property. Any shifting in the soil around your home can impact the ground underneath your driveway.
Don’t leave your investment and stability of your driveway’s asphalt up to chance. Give Cassidy Paving a call today at 866-978-9788 for an estimate on your driveway. Our certified, insured, and experienced asphalt driveway contractors can ensure that your asphalt driveway lasts many years.