I moved into my new home last year and had a new stopcock installed last Oct to replace the broken one that was in the spare bedroom. It wasn't a traditional stopcock, it was one of those red plastic dial ones. The plumber fitted a surestop in the airing cupboard. Last winter I heard loud banging in the pipework, but this stopped during the Summer. I haven't heard a sound for about 4 months, then a week ago as the temperature dropped the banging returned. The strange this I hear it in the early hours which is several hours after I've switched everything off. The only thing left switched on during the night is this surestop. I'm trying to remember what the plumber said, but I think he might have said it was easier to fit a surestop in the airing cupboard in the bathroom by the hot water tank as this is near the front of the bungalow,so nearer to the road where the main supply is. The kitchen is at the back of the property so maybe he thought it was more difficult to install a traditional one under the kitchen sink. I chatted to a plumber recently who said he'd had to remove a few surestops he'd installed as they can cause hammering. I did read up on them on the internet and it said the newer ones had eliminated this problem.Mine was only fitted less than a year ago, though I guess it could have been older stock. Has anyone experienced problems with surestops? Any advice as to what I might do next would be greatly appreciated. Many thanks.