Asphalt is an extremely durable and efficient choice for your driveway or parking lot, but there are some things you need to consider during installation and planning to ensure that it lasts. Appropriate depth, drainage, quality product, and efficient configuration are of huge importance, but the time of year that you choose for your paving installation can also play a big role in the final product and how it will wear.
Paving can be successful in varying conditions if appropriate measures for those conditions are taken and field experience does confirm that paving can be done under adverse weather conditions. However, the key to success is recognizing that paving practices that are successful in the warm summer months will not produce the same quality results in October through April. Ideally, the best temperature for successful asphalt paving is around 70-degree F. So, in Connecticut, that is typically late spring to early summer.
Hot asphalt mix is manufactured between 270-degrees F and 325-degrees F and can lose anywhere from 5-25 degrees during travel time to the site, depending on a number of factors.
When determining the available time for compaction of the asphalt mix, the temperature of the mix on the base after it has passed through the machine is the most important aspect. If the air temperature and/or the base temperature are colder than required for a quality install, the mix will cool too fast, making it nearly impossible to obtain the desired and required compaction level.
If the hot mix cools too quickly, it can also lead to a raveling surface, leaving a rough and rocky surface, reducing the life expectancy of your pavement. This type of surface will also retain water more easily, and as we’ve discussed several times, water is extremely detrimental to asphalt.
During an asphalt paving project, there are 3 temperatures that need to be monitored:
- Air temperature – This is the easiest temperature to monitor because this involves watching the weather and monitoring what the expected high and low temperatures will be for that day. If the temperature is expected to be, or go under, 50-degrees F, this is typically not an ideal day, because it will lead to the above problems.
- Base temperature – The base/ground temperature is even more pertinent to monitor. If the ground is too cold, the hot asphalt mix will harden up quickly. The base temperature should also be at least 50-degrees F and rising.
- Hot mix temperature – Before installing the mix on your base layer, we will need to check the temperature of the mix. The air temperature and weather conditions can certainly effect the temperature of the mix. You can gauge the temperature of your asphalt mix by taking the temperature in the haul truck, at the front of the laydown machine, and after the laydown machine has passed.
If any of these temperatures are lower than the required minimum, you are risking a failing pavement. The end product will likely ravel and fall apart because of improper compaction and installation. Monitoring temperatures and expected wind speed are important in new paving installation jobs, as well as patching repair jobs. If your paving contractor ensures you that temperature is not a factor during your paving project, this should be a big red flag to check out another contractor. As we continue to see a steady increase in temperatures, now is the time to begin planning your paving project and start contacting your professional paver! Contact EastCoat Pavement Services today for your free asphalt paving consultation!