Teflon tape, also known as plumber’s tape or thread seal tape, is commonly used in plumbing applications to create a watertight seal on threaded pipe joints. The longevity of Teflon tape depends on various factors, including the quality of the tape, the conditions it is exposed to, and how well it is applied.

In general, Teflon tape is durable and can last for a long time if applied correctly and used within its intended conditions. It is resistant to water, chemicals, and temperature variations. However, over time, exposure to certain chemicals, extreme temperatures, or mechanical stress can cause Teflon tape to degrade.

As a guideline, it is recommended to replace Teflon tape when you disassemble and reassemble threaded connections, as the tape may lose its effectiveness after being compressed and released multiple times. Additionally, if you notice any signs of wear, damage, or deterioration, it’s advisable to replace the tape to ensure a proper seal.

Keep in mind that Teflon tape is just one type of thread sealant, and there are other alternatives such as liquid thread sealants or pipe dope. The choice of sealant depends on the specific application and the type of materials being used. Always follow the manufacturer’s recommendations and guidelines for the specific product you are using.