Sealcoaters: Weather's Changing, Take Precautions

October 06, 2018

Sealcoaters: Weather's Changing, Take Precautions

Sealcoating at the end of the season can be a little tricky. Refined coal tar and Black Diamond Eco sealers are a better bet early and late in the season. Asphalt emulsion sealers are less tolerant of colder temps and shouldn't be used in the beginning and end of the season. Sealer should not be applied unless the temperature is at least 50° and rising, the asphalt temperature is at least 50° and rising, and there isn't a chance of heavy rainfall for 24 hours.

In colder temperatures, the particles that make up sealer will not fuse together. Refined tar particles will not soften sufficiently in cold temps--the fusion of particles (refined tar, clay & fillers) is necessary to form a continuous film. Sealers that do not form a continuous film will appear patchy and grey. Sealer that cures in poor conditions will lack durability and won't last. We recommend using additives in the fall, to reduce cure time. GemSeal Rapid set added to Fed Spec Coal Tar and Black Diamond sealers at 1-2 % is a great insurance policy with the cooler temps and moisture. 1 – 2% of GemSeal® Guard Flex can also be added to Black Diamond along with Rapid Set to improve strength.

With the right conditions and care, a proper coating can be applied throughout the sealcoating season--just watch your temps and use additives.




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