Weather related questions – asphalt driveway sealer
With the spring season in full bloom, the most common questions that I get ask about temperatures.
What should the temperature be to put down driveway sealer?
The simple answer is above 50 degrees.
The long answer is that the temperature should not dip below 50 degrees in a 24 hour period. As a general piece of advise, when sealing around that temperature, is that you give it at least 48 hours. The reason behind this is that the asphalt is much colder in the spring, and the fall, so you are relying on the air temperature and the sun to dry the sealer. While that usually is enough, the asphalt being up to temperature will greatly speed the drying process.
What time of year is best to seal your driveway?
In general, you will want to avoid early spring, late autumn, and obviously winter. In my area of the Midwest the answer will usually lie between April 15th until about October 15th. Different parts of the country will have this question answered differently. In parts of the south it is quite possible to use driveway sealer year round. In the northern or mountain areas your time-frame to seal your driveway is much shorter.
There is also another important fact to remember if you decide to hire a contractor. The later in the season it is, the more backed up most contractors get. Trying to squeeze your driveway in during the later parts of the season can often raise your price, or leave you waiting until spring. If you are wanting to get your driveway sealed by a contractor, it is best to have it done in the spring or early summer as these are the times when some are still looking to fill their schedules with work, and its much more likely to get it done sooner.
How long should the sealer be down for until it rains?
This is another question with many answers. The short answer is, until it dries. But that answer is deceptive. Most driveway sealers are made to dry from the top down, so while the top coating may be dried, the bottom layers that bond to the asphalt may still be wet. In the proper temperatures this will be less of an issue, but early or late in the year you need to have more time to let the sealer properly dry.
But, there is another fact to consider. If you believe that you will be facing really heavy downpours, I would put off any work for another day. A hard downpour can soften the coat, and remove the chemicals and minerals needed to harden the coat, leaving you with a mess. The way most people would fix this mess is to apply another coat, but it just makes it worse as the softened coat also has problems bonding with the asphalt.
If you are facing light rains, then as long as the driveway sealer is dry, it should be fine.
That answers most of the weather related questions that I receive on a daily basis. Hopefully this information will help you in your decisions in the future.