Hot Mix vs Warm Mix Asphalt

Hot Mix Asphalt (HMA) is the traditional process used when constructing asphalt pavements. At temperatures above 300ºF the petroleum based, asphalt binders become more liquid and flow more readily. This allows the aggregate to be thoroughly coated with the sticky binder which ultimately hardens to hold the aggregate together forming the final asphalt pavement.

Warm Mix Asphalt (WMA) by contrast uses water, water-bearing minerals, certain chemicals, waxes, organic additives and other technologies instead of the traditional petroleum based binders. Since WMA does not need the high temperatures to liquify an asphalt/bitumen binder it allows for cooler production temperatures at the asphalt facility and cooler temperatures at the job site. These lower temperatures actually allow for longer cooling times, extending the available pave and patch time. WMA also sees reduced emissions, odors and energy consumption at production facilities.

Even with the benefits the WMA offers, there are still some risks to consider. Compared to HMA, WMA is a relatively new technology and long term performance data does not exist in the quantity and quality of HMA. There are also production challenges in determining the proper binders and also heating the binders at a steady rate to ensure proper liquidity, flow and coating the aggregate with the non-petroleum based binders.

With nearly a century of paving experience you can be sure that Pavement Constructors has the knowledge and experience to guide you through your industrial or commercial paving project. If you have any questions about your asphalt project give us a call at 281-445-9900 or contact us today.