Last year I moved into a detached bungalow, and last winter I had trouble with noise from a clanging pipe. It seemed to stop when the weather got warmer in the Spring. A few days ago it went colder overnight and the clanging has returned. It happens in the early hours which is annoying as I'm still asleep. I tried not running hot water after 6pm and I didn't hear the clanging, however when I start putting the central heating on soon I will need to have it on til 9pm or so, so I will be woken in the night as I was last winter. I'll be calling a plumber soon to help, but can anyone give any advice beforehand so we can locate the problem quicker. Someone suggested it might be water hammer,but I am hearing knocking hours after I've turned everything off. 6 or so hours later. I'm guessing there's a pipe somewhere that is too close to a wall or joist, and as the pipe contracts it knocks the wall. It really is loud too! It's very difficult to locate where the noise is directly coming from. There is a radiator in the bedroom, against an outside wall so this seems to be the best place to start.Unfortunately I've bought a bungalow with no floorboards, but chipboard instead, so not easy to remove. I could end up paying someone to cut out several sections of chipboard. Has anyone heard of this noisy pipe problem, and does anyone have any advice in locating the likeliest places that I need to look at? Many thanks.