What Is PTFE (Plumber's) Tape?
The thin white tape you wrap around pipe threads so the joint doesn't weep. It fills gaps, it isn't glue.
Thin white thread-sealing tape (often called Teflon or plumber's tape) wrapped around threaded plumbing connections so they seal without leaking. Wrap two to three turns in the direction the nut tightens, and always strip old tape off before applying fresh.
What it actually does: threaded pipe joints seal metal-on-metal, and microscopic gaps between the threads weep water under pressure. PTFE packs those gaps and lubricates the threads so the joint tightens further with the same force. It is not glue. Tape on a cracked fitting or a compression joint (the kind with a brass ring) does nothing, and wrapping compression threads is the most common misuse.
Technique matters more than quantity: wrap clockwise as you face the end of the pipe (the direction the nut will turn), two to three turns, pulled tight enough that the threads show through. Wrapped backwards, the tape bunches and tears as the nut goes on. A $1–$2 roll lasts years; the pink-labeled "heavy duty" variant is thicker and better for larger fittings like shower arms.
Fixes that use this
Bathroom
Low Shower Water Pressure? Fix It in One Evening
Weak shower pressure is usually a mineral-clogged head, not your pipes. Soak it in vinegar, check the inlet screen, and know when it's something bigger.
Time20 min active + 1–2 hr soak Cost$2–$25 moderate