Installing an asphalt driveway in your yard is a more affordable option versus installing concrete, and it can last as long as 40 years when you take care of it properly. Asphalt is a flexible surface to give under the weight of your vehicle and under the freeze-thaw conditions of a northern climate. Here are some recommendations to build and maintain a solid, durable, and long-lasting flexible asphalt driveway.
Create a Solid Base
Before you can install your layer of asphalt, you need to prepare the ground soil and create a solid foundation where the asphalt layer will sit. One expert recommended that you think of the asphalt layer on your driveway as the veneer surface of a crushed gravel driveway. Much of the asphalt's strength and durability comes from the layers below it.
First, you will need to remove any topsoil from the site where you plan to install your driveway. If any existing paving material is already in place and you are planning to replace it, remove the materials with a Bobcat or a similar bucket loader. Be sure to remove enough soil to provide depth to fill in the appropriate filler base material and gravel for a solid base.
Test the Soil
Test the type of soil that exists in your foundation area to see if it is a well-draining and sandy soil, or if it is clay-like and poorly draining. You can complete a basic test on your own by taking a fistful of wet soil and squeezing it in your hand. If the soil falls apart as you release it, it has good drainage. If the soil stays clumped together, it is poorly-draining. You can also hire a professional engineer test your soil for its drainage characteristics.
For poorly-draining soil you will need to install an eight-inch layer of crushed gravel over the site. For well-draining soils, you will only need four inches of crushed gravel.
Smooth the gravel level and compact it using a compacting machine. This presses the angular edges of the gravel together, creating an interlocking and strong layer. Now your base is ready for the asphalt to be installed.
Slope the Finished Surface
When you install the asphalt over the top of the gravel, you will only need to install two to three inches of asphalt mixture compacted over the surface to withstand the weight of traffic. The asphalt surface does need to be sloped at a slight angle to provide a grade where rain water and other moisture can run from its surface. Allowing areas on your asphalt surface where water can pool can cause damage to the asphalt. During winter, freeze-thaw cycles can cause the surface to crack apart. Instead, you will want any water to be able to flow off the sides of your asphalt into surrounding soil.
It is recommended to create a slope to your driveway of at least one-fourth of an inch for every foot of length. You can create this slope to extend from one end of your driveway to the opposite, or create a slight ridge down the entire middle of the driveway, with the sides sloping downward from the center ridge. Make sure the entire surface is smooth and does not have any slight dips or indentations to prevent pooling of water.
Clean Up Vehicle Spills
After your surface has been installed, it is necessary to clean its surface of any vehicle spills as they occur during its use. If you allow vehicle fluids, especially oils and gasoline to remain on its surface, they will cause the tar emulsion within the aggregate mixture to break down, allowing your surface to fail. If this occurs, you will notice the emulsion will wear away to leave behind only the aggregate, which will soon crumble apart.
Use an asphalt degreaser and cleaner to scrub and rinse fluid spills from the surface of your asphalt. Use a scrub brush to clean the surface, then rinse it clean with your garden hose. Complete this inspection and cleaning routine on a regular basis and you can keep your asphalt from receiving this type of damage.
If you're not confident in your ability to fulfill these tasks, hire a residential paving company.