This is happening to me. Only when I flush the toilet in my master bath. Tapping sound continues for quite a long period (about 1/2 hour). Is this something I need to have repaired or can I just live with it?

Knocking, popping, creaking and crackling pipes are a common complaint, especially in colder weather. I can tell you what's happening and take the mystery out of it but you're not going to like the repair. When a draw is made on a hot water line the line expands against a pipe strap next to a stud and when you drain hot water from your tub or shower it goes into a chase that is a little cooler then room temperature. The heat expands the pipe causing it to rub against the stud to which it is pipe strapped. This is the sound you hear. As it cools it contracts and the noise is heard again. To repair it you must tear open the walls and locate the pipe strap that's causing the problem and shim it tight. Most people when they learn what causes it just elect to live with it. Good luck and thank you for rating my answer. Tom

Tom, they said it was a toilet, not many piped with hot water.

Tom, they said it was a toilet, not many piped with hot water.
That's true, however there is still running water in the line supplying the toilet tank. That cbe expanding and contracting , Iagainst a stud, can you come up with any other reason? Back to you, Tom

Lets try again. Where is the tapping sound? In the toilet, wall? Inside a cabinet? In the floor? Do you have a circulating pump for the hot water? Flush the toilet and feel the supply line to the tank. Hot or cold?