Once again, the summer season is upon us and as sure as the sun is going to shine, questions regarding the installation of sealant at elevated temperatures is eminent. There will always be a new wave of novice sealant installers who require education on the effects of temperature on sealant under adverse conditions like 95°F and 90% relative humidity. It is hard enough to breathe under such conditions, so we understand the need for answers, and are always available to ease the difficulties encountered with excessively hot weather.
As we can see from the table above, the effects of temperature and humidity play a completely different role depending on the type of sealant being applied. It is important to understand the cure characteristics of a sealant before starting a project. Armed with the knowledge of how the particular sealant being used cures, a contractor can better plan and manage a project. And in the process, minimize inefficiency due to issues that sometimes arise when temperature and humidity extremes catch you by surprise.
Unfortunately, a manufacturer’s literature does not always predict sealant behavior under all environmental conditions. Most literature refers to standard conditions of 75°F and 50% relative humidity when listing sealant properties. Lower and upper service and application temperature ranges are generally listed with notes to contact technical service when venturing outside of those ranges. In the real world, environmental conditions are in a constant state of flux with day and nighttime temperatures sometimes shifting radically.
With deadlines and schedules to meet in the commercial construction process, and the inability of mother nature to cooperate with the workflow schedule, construction processes are sometimes carried out under les than optimum conditions. Pressure to meet deadlines often forces work to continue in the face of compromise for quality. The good news is, when faced with challenging conditions, the more knowledge of the materials utilized in the construction process, the less likely a serious problem will surface.
The bottom line is that warm weather can be your friend, as well as your enemy depending on the knowledge you possess of the material you may be working with. Reference the table above for general guidelines on the cure characteristics of sealant based on curing chemistry.