We are experiencing a very LOUD noise when the hot water is turned on in the downstairs 1/2 bathroom sink. The noise sounds like it's vibrating the whole house. This only occurs in this bathroom... no other sink nor any bathtub... nor outside faucet.

We are on city water.

The faucet is one of those single knob fixtures not separate knobs for hot/cold.

This does not happen as soon as the knob is turned on for Hot, but a few seconds after the warmer water starts coming out. There is no sputtering of the water... just a horrendous noise.

Please help... driving us nuts!

Thanks in advance,
Billy

If you have cutoff valves under this bathroom sink try turning off the hot water side and then open the faucet to see if you get the noise. Then do the same with the cold water and see if the hot make a noise. If either of them do then you probably have a problem with a washer on one of the cutoffs under the sink, it will be the one that rattled when the other one was off. Or it is possible it is a part in the faucet itself that is vibrating that causes the noise. Replace what you can and see it it stops the noise. Let me know if this advise helps.