It might all look the same when it’s dry, but did you know that there are dozens of different types of asphalt mixes, each with its unique blend of binding material and aggregates. Which one you’ll need for your asphalt repair services depends on the job, location, and time of year.
Here’s more on custom asphalt blends and what they are used for:
Hot Mix Asphalt
Hot asphalt is as described – hot. This asphalt mix is heated to around 150°C and was designed to be poured while hot. It’s most often used in large-scale commercial applications, like roadways, parking lots, and airports, but you may see it used for residential purposes as well.
Hot mix asphalt is best known for its flexibility, durability, weather resistance, and impermeability. It also has the fastest cure time of any other type of asphalt, making it a good choice for busy areas. However, it is more expensive than other asphalt mixes and can be challenging to work with due to temperature restrictions.
Hot asphalt mixes can be broken down into three categories: dense-graded, stone matrix asphalt and open grade mixes. Depending on the mixture of aggregate particles used, dense-graded HMAs are further classified as either fine-graded or coarse-graded.
Fine-graded HMAs are virtually impenetrable, and this is what you will typically see on highways and high-traffic roads. Coarser HMAs are sometimes used as a base underneath a fine-graded top layer.
Cold Mix Asphalt
At the other end of the spectrum, we have cold mix asphalt. As the name implies, cold asphalt does not have to be kept hot. However, this type of asphalt mix is not a direct substitute for hot (or warm) asphalt. Additives in the mix make cold asphalt malleable, even at cold temperatures, but it takes longer to cure and is generally not as strong as hot asphalt.
Cold mix asphalt is typically only deployed for temporary asphalt repair services, in cases like cracks or potholes, when temperatures are too cold for hot or warm asphalt mixes.
Warm Mix Asphalt
Warm mix asphalt is a compromise between hot and cold asphalt mixes; it shares some of the same advantages of hot mix asphalt – it’s weather-resistant, pliable, and impermeable – but it doesn’t need to be kept as hot. Binders and additives added to the asphalt mix make it more adaptable to lower temperatures, reducing the energy required to keep it hot and the harmful fumes discharged when poured.
This asphalt is suitable for a wide range of uses, including commercial paving works, in locations with poor ventilation, and for smaller residential projects.
So, what type of asphalt mix do you need for your asphalt repair? It will depend on the extent of the damage and weather conditions. Hot or warm mixes are preferable for long-term asphalt repairs; however, if temperatures are too low, a CMA may be used as a temporary solution until such time as an HMA can be installed.