Why do chip seals fail?

Oil and stone, more properly known as a chip seal, fail for a variety of reasons but, more often than not fail when the stone does not properly adhere to the pavement. This stone loss is most commonly a result of a misstep in the initial installation.

Installation factors that can attribute to stone loss include:

Applying the treatment in the wrong weather
An improper emulsion application rate
An improper aggregate application rate
Placing the aggregate too late and after the emulsion has broken
Dirty aggregate

Aside from timing and application rates, there are five steps that should be taken during the construction process:

Sweeping before the emulsion application
Spraying the emulsion
Spreading the aggregate
Rolling the aggregate
Sweeping the excess stone off of the road surface a day or two after the chip seal is placed.