A question that is often asked is, "is it too cold to sealcoat my asphalt parking lot? " The rule of thumb, is that the sealcoating season typically runs from April 15th to November 1st.
Some contractors stretch their season by starting April 1, the day most sealcoating manufacturers open for the season.
The ideal time to apply asphalt sealer is from May 1st - October 20th. This is because the pavement has warmed sufficiently until the last week of April. Sealcoating anytime after October 31st, the nighttime temperatures fall below 40 degrees. This could cause problems with a water based asphalt sealer.
Pavement sealers are best applied when the temperatures are a MINIMUM of 55 degrees and RISING and do not fall below 50 degrees for 48 hours after application. This allows ample cure time for the pavement coating. Since you need 24 hours for asphalt sealer to fully cure on the pavement surface before allowing traffic, temperatures are extremely important.
While it is tempting to accept and complete the work in various temperatures, in my 25+ years of seal coating experience, we know we would be doing these clients a disservice.
If a seal coating contractor attempts to convince you to seal coat anytime after November 7th, please follow these simple steps:
1.) Require an irrevocable warranty of 1 year which is not negated with terms and conditions or declaimers releasing them of performance if the coating fails due to cold temperatures.
Many sealcoating warranties will specifically state there is no expressed or implied warranty for sealcoating work completed outside the time period of April 1st - October 31st.
Contractors motivated by greed will attempt to convince you to complete the projects, knowing full well it is going to fail, only to try to put a kick out clause to protect themselves in the spring.
2.) Require a 20% contract amount retainage until April 1st when the area can be inspected for premature wear and tear. 3.) DO NOT provide a deposit under any circumstances as a cash-strapped seal coating contractor (The same type which would knowingly seal asphalt during cold temperatures) may suddenly share this authors opinion on not sealing during cold temperatures after your check has cleared and the available funds are in their checking account giving them leverage over the schedule.
Bottom line is, if pavement sealer is applied after October 31st and the overnight or daytime temperatures fall below freezing with-in 30 days of application, the pavement sealer is going to wear off the asphalt by the spring.