I'm no plumber by the way. The pipes in my living room ceiling have been driving me mad for a couple of years (since I moved in), when ANY hot or cold valve is opened or closed anywhere in the house the pipes make a loud thud/squelch/bang noise. So today I'd finally had enough and pulled some ceiling down to have a look, I've tried holding all the these pipes and connections tight by hand but they all kind of expand and make a noise when a valve is opened and then again when its closed. I have a little more exploring to do in the ceiling but so far the cause may just be all of the connections expanding and contracting at the same time that's causing the noise. Although, the next hole I cut will get me under the en suite so maybe I'll find something noisy in there. Anyway, is there anyway to quieten down this lot, do I need better brand connections? Do I need to replace it for copper where I can? Or what?