The answer to this question is a little more complicated than you might expect. Silicone sealant dries fairly quickly, but that doesn’t mean it’s ready to be inundated with water or exposed to the elements—it needs to cure first. Find out the difference between drying and curing and how long they take in this article from the experts at Adfast.
The difference between drying and curing
Although the terms are often used interchangeably, there is a big difference between drying and curing. Drying is the initial phase where the ambient humidity comes into contact with the silicone, leaving it dry to the touch. Silicone sealant dries fairly quickly, usually taking around 30 minutes to an hour.
However, silicone sealant is waterproof only after it cures completely, which takes significantly longer. Curing involves a series of chemical changes that take place once the silicone is exposed to oxygen. Silicone sealants can take anywhere from a few hours to 21 days to cure, depending on how much sealant you use. A thicker coat of sealant will take longer. There are also a few other factors that can influence curing time.
Factors that influence curing time
The type of silicone
Specialized silicone sealants tend to have a more complex chemical structure that requires a longer curing time. These include sealants that are designed to withstand high temperatures or expand upon application.
Humidity
It may seem counterintuitive, but humidity actually accelerates curing time. That means that silicone will usually cure faster in the summer than in the winter, when central heating dries out the air. When using silicone sealant in the bathroom, don’t be tempted to turn on the fan to help it cure faster—it will have the opposite effect. Instead, try putting a humidifier in the room.
Temperature
Warmer temperatures generally lead to faster curing times, partly due to the fact that they usually involve higher humidity. However, regardless of the ambient temperature at the time you undertake your project, it’s not a good idea to try to help the silicone cure faster by applying direct heat to it. Heat softens silicone and can even melt it, which will have a negative effect on the longevity of your sealant.
Adfast: your resource for high-quality silicone sealant
When applying silicone sealant, don’t assume it’s ready once it’s dry to the touch—it needs to cure completely before it can be exposed to moisture. It’s always a good idea to check the packaging to determine the specific drying and curing time for the product you’re using.
Adfast is a company that provides high-quality sealant and insulation for residential and commercial use. Our silicone sealants are long-lasting, low in VOCs and available in a wide variety of colours. Contact us for all of your sealing and caulking needs!
