How Long Does an Asphalt Driveway Last in Minnesota?

One of the most common questions we get from homeowners considering a new asphalt driveway is simple: How long should it last?

For a properly constructed asphalt driveway in Minnesota, 15 to 20 years is a good benchmark. That doesn't mean a driveway can't last longer. We regularly see driveways that have exceeded 20 years and are still performing well.

The lifespan of an asphalt driveway depends on more than the asphalt itself. Base preparation, native soil conditions, asphalt thickness, drainage, edge support, maintenance and even how the driveway is used can all affect how long it lasts.

A Long-Lasting Driveway Starts Below the Asphalt

When we replace an asphalt driveway that has failed prematurely, poor base preparation is one of the most common problems we find.

In our area, a minimum of 4 inches of Class 5 aggregate base is a common industry standard, but that should be considered a minimum rather than a one-size-fits-all specification. Native soil conditions ultimately determine how much base is needed.

Some properties have naturally stable soils. Others have areas of clay, organic material or unstable soils that need to be removed and replaced with additional aggregate.

We've removed driveways with plenty of asphalt that still failed because the pavement was installed over an inadequate base. Simply installing more asphalt doesn't correct what's happening underneath it.

That's why proper sub-cut and base preparation are so important.

Why We Don't Always Pave a Driveway Immediately After Preparing It

At Valley Blacktopping, there is often a period of time between preparing a driveway and installing the asphalt.

That's intentional.

Once the driveway has been excavated, the necessary Class 5 has been installed and the driveway has been graded and compacted, we want the base to become firm and stable before paving.

During this period, homeowners can drive and park on the prepared driveway. In addition to being convenient for the homeowner, that traffic helps work the aggregate and gives us an opportunity to identify areas that may need additional attention before they're covered with asphalt.

A solid base also makes a difference during paving. If the underlying soils or aggregate are unstable, paving equipment can sink or move as it travels across the driveway, making it much more difficult to maintain a consistent asphalt thickness.

We want the driveway solid before we pave it.

How Thick Should a Residential Asphalt Driveway Be?

For most residential driveway replacements, Valley Blacktopping typically installs 2.5 to 3 inches of asphalt.

Thickness matters, but the number by itself doesn't tell the whole story.

We've removed driveways where the exposed edges measured 3 inches or more while portions through the center of the driveway had only about an inch of asphalt. A driveway can therefore appear to have adequate asphalt at the edges without having a consistent mat throughout the entire paved area.

Proper grading, a stable base and consistent paving practices all contribute to maintaining the intended asphalt thickness.

It's also important not to assume that a driveway must have 3 inches of asphalt to reach the 15 to 20 year benchmark. We work with homebuilders whose specifications call for 4 inches of aggregate base and 2 inches of asphalt, and properly constructed driveways using those specifications can still provide 15 to 20 years of service.

Asphalt thickness is important, but the entire pavement structure has to work together.

What Does Minnesota Weather Do to an Asphalt Driveway?

There is no getting around Minnesota's freeze and thaw cycles.

Our pavement experiences significant temperature swings throughout the year, and some movement is inevitable. Modern asphalt mixes used in Minnesota are designed with our climate in mind, including resistance to thermal cracking during cold weather.

One time of year homeowners should pay particular attention to their driveway is spring thaw.

As frost comes out of the ground, underlying soils can temporarily become softer and less supportive. Even a properly constructed driveway can be more susceptible to damage during this period.

Use some common sense with unusually heavy or concentrated loads during spring thaw. Dumpsters, heavy trucks, trailers and similar loads can put significantly more stress on a driveway than normal passenger vehicles.

Once the ground firms back up, the pavement structure regains the support it was designed to have.

Supporting the Edges of Your Driveway Matters

One of the simplest things homeowners can do to protect a new asphalt driveway is also one of the most overlooked: support the edges.

After paving, the surrounding material should be backfilled so that it is flush with the top of the asphalt.

Asphalt edges without proper support are more susceptible to cracking and breaking, particularly when vehicles drive close to or off the edge.

Properly backfilled edges provide lateral support and help protect one of the driveway's most vulnerable areas.

Does an Asphalt Driveway Need to Be Seal Coated?

We don't consider sealcoating mandatory maintenance.

Homeowners may choose to sealcoat their driveway, but sealcoating is optional.

The maintenance we do recommend is much simpler: fill cracks as they develop.

Cracks allow water into the pavement structure. Keeping them filled helps limit water infiltration and can slow further deterioration.

You don't need to overcomplicate asphalt maintenance. Proper construction on the front end, supported edges and addressing cracks as they develop go a long way toward getting a reasonable service life from your driveway.

Can an Asphalt Driveway Last Longer Than 20 Years?

Absolutely.

The 15 to 20 year figure is a benchmark, not an expiration date.

We've seen plenty of Minnesota driveways continue performing beyond 20 years. Long-lasting driveways typically have several things working in their favor: good native soils or properly corrected soils, sufficient aggregate base, good drainage, adequate and consistent asphalt thickness, supported edges and reasonable maintenance.

There are also variables outside a homeowner's control, which is why we don't believe in promising that every asphalt driveway will last a specific number of years.

The goal should be to construct the driveway correctly and give it the best opportunity for a long service life.

How Do You Know When an Asphalt Driveway Needs Replacement?

Age alone shouldn't determine when you replace a driveway.

A 20-year-old driveway that is structurally sound doesn't need to be replaced simply because it reached a certain birthday. Likewise, a much younger driveway can require replacement if there are significant underlying problems.

Some of the signs we look for include:

• Significant settlement, particularly where the driveway meets the garage

• Large cracks throughout the driveway

• Widespread alligator cracking

• Loose pieces of asphalt

• Areas where portions of the pavement have broken away or are missing

An isolated crack doesn't necessarily mean a driveway has reached the end of its useful life. When deterioration becomes widespread and the pavement begins breaking apart, however, continued repairs may no longer make sense.

So, How Long Should You Expect Your Minnesota Asphalt Driveway to Last?

Plan on 15 to 20 years as a reasonable benchmark.

A properly constructed driveway can certainly last longer, but longevity begins well before the asphalt is installed.

The quality of the native soils, proper sub-cut, sufficient Class 5 aggregate base, drainage, a stable surface before paving, consistent asphalt thickness and proper edge support all play a role.

At Valley Blacktopping, we've been paving residential driveways throughout the Twin Cities since 1976. After 50 years in the asphalt business, one thing hasn't changed: a good finished driveway starts with what you can't see underneath it.