The expiration or best before date is an indication of how long a product can be guaranteed to be effective when stored under certain conditions. After a sealant has expired, the properties of a sealant can’t be ensured, however a sealant stored under ideal conditions can remain effective for many months after its expiry. Conversely, sealants stored in unheated buildings or overly hot conditions can expire long before the stated expiry date.
Common symptoms of expired or incorrectly stored sealant include hardening in the tube or delayed curing, and in extreme cases some sealants may never cure.
Sealants need to be stored in a dry, well-ventilated area, away from heat and within a temperature range specified by the safety data sheet, but usually between 5-25°C. As the date printed on the tube is essentially a guide that cannot take into account storage and transport conditions, expired sealant may be perfectly fine to use for many months after this date. Conversely, a sealant within its date may have prematurely expired.
For these reasons, it’s important to only buy sealant from reputable sellers who you trust to store their product correctly. Here at Grove, we store all of our sealant in climate controlled conditions to comply with the storage recommendations of each manufacturer.
If the sealant is still soft in the tube, guns and tools easily, and cures within the specified timeframe, then an expired sealant should be perfectly fine to use. Many people will have used prematurely expired sealants without realising and without any issues whatsoever. For simple sealing jobs, using expired sealant can be a very cost-effective way of completing a job, but for critical applications we would recommend using in-date sealant that has been purchased from a source that you trust.