Asphalt Driveway

This asphalt driveway is eight years old and has survived punishing frost heaves with little cracking. PHOTO CREDIT: Tim Carter

DEAR TIM: I grew up with an asphalt driveway, but my husband had a concrete drive. We’re debating what type to install as our current drive is in horrible shape. My contention is the asphalt driveway cost will be less than concrete. But my husband doesn’t want to mess with asphalt driveway sealer every year or so. What would you install at your home? What are the pros and cons of a new asphalt driveway? Lisa G., Burbank, CA

DEAR LISA: Let’s start by saying I’ve had both types of driveways at homes I’ve owned as well as a third possibility that you didn’t mention. I’ve had great success with all the driveways with respect to their ability to withstand heavy trucks, wear and tear, and virtually no maintenance. Yes, I said little maintenance with an asphalt driveway.

Asphalt driveway paving is a huge business, and you’ll probably discover many different contractors in your area that specialize in this trade. Asphalt is fairly easy to install if you have the right machinery and a good crew that understands the material.

Asphalt is not too much different than concrete with respect to how it’s made. Both asphalt and concrete are made with stones and sand. But the binder that locks them together is completely different. Concrete uses Portland cement, while asphalt or blacktop uses asphalt cement. Asphalt is a very unique compound because at normal temperature ranges it can be flexible. This can be an advantage with paving.

When crude oil is low in price, the cost of an asphalt driveway is usually less than concrete. This is not always true as there are so many variables associated with each job. You simply have to get an asphalt driveway estimate along with one for concrete to make your decision, if it’s purely a cost issue.

But there are other things you should consider. Asphalt drives can contribute to staining of floors in your home if you’re not religious about taking off your shoes at the door. You can track in the oils from asphalt drives, as well as asphalt driveway sealer, if you leave your shoes on and walk around the house. My in-laws home had gorgeous white vinyl flooring in their kitchen that had yellow pathways created by the oils tracked in from the asphalt.

Sealing an asphalt driveway doesn’t have to happen as frequently as you might think. The current home I’m in has an asphalt driveway that’s eight-years old. It’s in nearly perfect condition, and has never been sealed. It’s absolutely true that sealers will help prevent water from seeping into tiny cracks in the surface, but I see none of those on my driveway.

Large asphalt roadways are not sealed, but they are sometimes coated with a rejuvenation product that helps extend the life of the asphalt cement that holds together the rocks and sand in your driveway. Ask your local asphalt contractors what they know about the rejuvenation coatings.

If you decide to go with an asphalt driveway, you need to understand where they derive their strength. Because the asphalt can actually move when it gets hot, the crushed gravel beneath the drive must be deep and well compacted. The soil under the gravel should be very strong, well drained and compacted. It’ not a bad idea to install a geo-textile fabric between the soil and the crushed gravel.

Asphalt driveway construction is a true science. I would install no less than 8 inches of crushed gravel under any asphalt drive I was installing. It should be installed 4 inches at a time and each layer well compacted. The gravel should extend at least 6 inches beyond the final edge of the finished asphalt if you want the edged of your drive to withstand heavy loads with no cracks.

If you’re considering asphalt driveway resurfacing, understand that you have several things that need to be thought out. Cracks in existing paving can telegraph through the new surface. If you want a perfectly smooth driveway for years, you may want to start over putting the new asphalt on freshly compacted gravel.

Adding one layer of asphalt on top of another can be problematic at sidewalks, garages, etc. The existing driveway may have great drainage away from these abutting surfaces, but the new driveway may create ponding issues. Be sure to discuss this possibility with your contractor. You want great drainage and no miniature ponds on your new drive.

Do NOT seal a new asphalt driveway for at least a year. You don’t need to seal it until it starts to turn gray or you see that the asphalt cement has worn off many of the small rocks.

You want a driveway that puts heads on a swivel? Go with a tar and chip driveway. It’s a hybrid asphalt driveway where liquid asphalt cement is squirted onto gravel and small colored stone chips are broadcast into the hot tar. Once it cools, you have a magnificent surface that wears like iron.

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