How Long Does Caulk Last In The Tube After It Has Been Opened?

Caulk is a material that many DIYers have in their toolbox. From caulking baseboards and trim for expert-looking results to preventing water damage, this tool is one of the purchases where you get what you pay for. Even though you might buy a tube of caulk for one small project, you can use it repeatedly for many household purposes as they come up — at least for a time. As it turns out, caulk can eventually expire. After it's been opened, it can last from a few weeks to a few months, depending on storage conditions.

Once you open caulk, air and moisture naturally start the curing process. Any caulk in the nozzle will harden and create a plug, usually within a few hours or days. While this plug generally will keep the remaining caulk in the tube usable for a time, using a specialized caulk cap will create a much more airtight seal, significantly extending the caulk's shelf life. This method will usually render the remaining caulk usable for 30 to 60 days.

If you try to use previously opened caulk and it's difficult to squeeze out or looks like the material has separated into different substances, that is a good indication that it's expired and should be thrown out. Likewise, if it's past the expiration date on the tube, you should probably throw it out and invest in a new one. Using expired caulk will result in poor performance, ultimately failing to create a reliable, watertight seal.

Keeping the tube of caulk in the right temperature conditions will help keep it usable for as long as possible. You'll want to aim for a consistent temperature of roughly between 40 and 75 degrees Fahrenheit, so skip the garage and aim to keep it in the basement or closet. You'll also want to ensure that you're giving it the best seal possible to extend its life, so choose one of the best caulk caps you can find instead of trying to plug the opening with a makeshift solution like a nail or a piece of tape.

If you know you won't be using your caulk anytime soon and want to maximize its longevity, you can also double-seal it. After placing the caulk cap on the tube, put it into a Ziploc bag. Remove as much as you can from the bag before sealing it, then store it upright. This extra step creates a secondary barrier against air and moisture, helping to preserve the caulk for up to a year or more, depending on the type. And if you're feeling extra diligent, there are other genius tricks for storing a caulk tube so it doesn't dry out that you can also try to hopefully prolong the time before your next trip to the hardware store.