This legnth of pipes carries water to the kitchen sink and a small bathrron with sink and toilet. When the toilet is flushed and at the point that the water is at it's end of filling the tank there is a sharp noise in the ppes somewhere and a loud viabration is the system of ppes I guess. It's hard to describe but almost like when the water is finished filling the noise is like the pipe is hitting against the wood that it is supposed to be tied down to. It's hard to look at what is going on as all of these pipes are in the crawlspace foundation area of the house and very difficult to get to. I am wondering if I should be worried about something leaking or is this common with houses in thier 50+ year old range.
Could be a loose pipe, but could also be caused by the fill-valve in the toilet. This happens frequently with the ball and arm type valves. Try flushing the toilet and then raise the ball and arm by hand. Sometimes, the ball gets to moving with the water refilling and it bounces instead of just shutting off the valve.
If you have never made a mistake, you haven't done much.