What is Seal Coat, and is it Effective in Arizona?

Arizona (Phoenix and Tucson specifically) is known for its nearly year-round sunshine and warm, dry weather. And while you might love the warmth and sun, your property might not. The constant beams of UV rays are slowly breaking down Arizona’s asphalt assets causing cracks, ravelling, and other oxidative damage. 

A common approach to preventing this damage is seal coating.

What exactly is seal coating? Is it effective in the intense Phoenix and Tucson’s heat? We’ll explore these questions and some alternatives to seal coating.

For years, a seal coat has been the go-to option for protecting and preserving asphalt. The concept is fairly straightforward: workers apply a thin layer of protective material over the asphalt surface to shield it from the elements and improve its overall appearance.

While it sounds like a good solution in theory, experts have learned through years of experience and countless projects across Arizona that the theory doesn’t always align with reality.

One thing that makes seal coat so widely adopted is its perceived affordability. For decades seal coats have been viewed as a cheap solution that should be applied to asphalt every 2-3 years.

However, diving a little deeper into the economics and effectiveness of seal coats shows that while they might seem affordable, the reality is quite different. As new and more innovative products have been introduced to the market seal coat has to be reevaluated to ensure it’s still effective — especially in a harsh environment like Phoenix and Tucson. 

The question of whether or not seal coat is worth it in Arizona is worth it is nuanced. 

Luckily, we have a nuanced answer. The truth is, seal coat isn’t very effective in most cases.

Put simply, seal coat does give your asphalt some protection. It helps out to an extent, mostly by shielding it from the sun’s UV rays, which can cause asphalt to become brittle and crack over time. It also gives the surface of the asphalt a fresh, black appearance for a short period of time. 

But while seal coat does offer some benefits, they’re relatively modest and often short-lived, especially in places like Phoenix or Tucson, where the climate is unforgiving.

The extreme heat, combined with intense monsoon seasons means that the protective layer initially provided by a seal coat wears away much faster than expected. And without continuous reapplication, asphalt is left vulnerable. 

The bottom line: seal coat does provide some extension for asphalt’s life and is better than doing nothing. However, to receive any benefits from seal coat its much more expensive over time than expected and there are more effective treatments available.

A lot of asphalt owners are skeptical when they hear this answer. The professionals at Advanced Reserve Solutions were when we first approached them to discuss pavement preservation. The video below outlines their opinion of seal coats and what they recommend Arizona’s HOAs do instead:

If seal coat isn’t the number one choice for preserving Arizona’s asphalt, what’s the alternative? High Density Mineral Bonds.

High Density Mineral Bonds, sometimes referred to as HA5, have displaced seal coats in many communities in Arizona. Unlike traditional seal coats, HA5 is specifically engineered to address the shortcomings of conventional sealants.

What makes HA5 different? It all comes down to the formula. Without getting too technical, the way HA5’s base emulsion is manufactured allows it to bond with asphalt’s surface more effectively than a traditional seal coat.

This means HA5 lasts longer and provides more protection for the asphalt binder which would otherwise become weak and brittle as its exposed to the sun’s intense UV rays.

Here are a few more reasons why HA5 is better suited for the area:

• Designed for extreme climates: Summer temperatures in Southern Arizona regularly exceed 110°F, meaning asphalt can reach scorching temperatures that accelerate wear and tear. Traditional seal coats, which sit mostly on the surface, can’t withstand that heat. HA5 is formulated for these conditions. It was designed and tested in the Mojave and Sonoran deserts to withstand the intense conditions.

•  Superior UV resistance: On average, the sun shines more than 300 days a year in Phoenix. That constant exposure to UV rays is a key factor in asphalt degradation. Over time, UV exposure causes the asphalt binder to oxidize and harden, causing the asphalt to become brittle and crack. Seal coats provide some protection for a short period of time, but HA5 protection lasts much longer. The High Density mineral composition of HA5 creates a more robust barrier against UV rays, slowing the oxidation process.

• Longevity and cost-effectiveness: Another major advantage of HA5 is its longevity. Most seal coats require application every one to two years (if not sooner in Phoenix and Tucson’s demanding environment). HA5 lasts much longer, providing property owners with extended protection and lowering the frequency of maintenance. That longevity translates directly into cost savings.

But don’t just take our word for it: Curt Balko, HOA President of La Canada in Phoenix, moved from the traditional seal coat to HA5 after spending thousands on reapplying seal coat every three years.

With HA5, the HOA only has to apply every five to six years, resulting in a 50% reduction in reserve costs. “Putting this product on eliminated some of the repairs we would have had to do, so it saved us money there too,” Curt said.

Mimi Bales, HOA President of Chapparal Vista Estates in Phoenix, switched to HA5 after she and the board realized how much longer the material lasted.

“In the past, our roads had the usual seal coat application done, and we just weren’t happy with it,” Mimi said. She said the board and residents are excited about the longevity of the material and the cost savings it provides.

Let’s talk about the elephant in the room: cost. While seal coat might seem like the budget-friendly choice at first glance, the real story emerges when you look at the bigger picture.

Seal coat’s initial affordability is appealing, but the reality is that property owners often find themselves reapplying seal coat every 1-3 years . This dramatically drives up the long term costs.

On the other hand, HA5 typically performs well for 5+ years, even under our demanding desert conditions.

What does this mean for your bottom line? Over a 30-year period, you might need up to 15 seal coat applications compared to just 5-6 HA5 treatments. Do the math, and you’ll find that seal coat could end up costing nearly twice as much as HA5 in the long run.

Don’t just take our word for it – several Phoenix-area communities have worked with their reserve analysts to calculate the potential savings. The results? Similar to what Curt Balko at La Canada HOA discovered: significant reductions in reserve costs and fewer repairs needed overall.

Convincing your board or community to switch from traditional seal coat to HA5 might seem challenging, but we’ve found that success comes down to three key factors that resonate with Arizona’s property owners:

1. It’s all about education. Just as we’ve explained the science behind UV damage and asphalt preservation, help your stakeholders understand why protecting your pavement assets is crucial in our harsh desert environment. Show them why HA5’s formula is specifically engineered for conditions like ours, unlike traditional seal coats.
2. Let the numbers do the talking. Work with your reserve analyst to project the long-term financial impact. As we’ve seen with communities like Chapparal Vista Estates, the cost savings over time can be substantial. When board members see the potential impact on their reserves, the decision often becomes much clearer.
3. Finally, consider the convenience factor. Ask your community members a simple question: would you prefer having your streets disrupted every couple of years for seal coating, or just once every five to six years with HA5? In our experience, Phoenix and Tucson property owners appreciate fewer disruptions to their daily routines, especially during our hot summer months.

HA5 is more than just an alternative to a seal coat — it’s a superior solution, tailor-made for the challenges of Phoenix’s climate. From its enhanced UV resistance and long-lasting durability to its cost-effectiveness, HA5 gives Phoenix property owners a comprehensive solution that traditional seal coat can’t match.

Want to learn more about HA5? Contact the experts at Holbrook Asphalt for more information.