Hi,
I get a water hammer when I flush the toilet and open the COLD taps, tried releasing air out of the pipes by shutting the water off and opening the taps but still no luck, if it helps this happens when I turn the cold taps halfway or full if i turn it a little it doesn't make the hammer noise.
Been living with this for months now and fed up with it! (not had any work done in the bathroom recently either)