Yes, PTFE tape is waterproof. PTFE (polytetrafluoroethylene) is a highly inert material known for its excellent chemical resistance and waterproof properties. When properly applied to threaded pipe connections, PTFE tape forms a tight seal that helps prevent leaks, even in environments where water pressure is present.

PTFE tape is commonly used in plumbing applications precisely because of its ability to create waterproof seals on threaded fittings. It is resistant to water, oils, solvents, and most chemicals, making it suitable for a wide range of plumbing and industrial applications where waterproofing is essential.

However, it’s important to ensure that PTFE tape is applied correctly to achieve its waterproofing properties effectively. This typically involves wrapping the tape around the male threads of the fitting in a clockwise direction and applying enough layers to fill any gaps and create a secure seal when the fitting is tightened.

Overall, PTFE tape is a reliable choice for waterproofing threaded pipe connections and is commonly used in plumbing systems to prevent leaks and ensure water-tight seals.