Is Breaking off icicles from the gutter on Shabbos permitted, or is it a problem of kotzer, since it grows from the water in the gutter, similar to a fruit that grows from a tree and a fetus inside a cow? Thanks
It is not kotzair because the icicles don’t get their nourishment and grow from the gutter. If anything it is an issue of sosair, because it is attached to a building. In fact the Magen Avraham 320-16 says that it should not be removed because of sosair. The Mishna Berura 320-36 however brings a number of other Achronim who argue with the Magen Avrohom and say that although the ice is presently attached to the building because it is frozen, however it isn’t considered integrally attached to the building, because as soon as it melts it will detach. Therefore they say that it is permitted. The Mishna Berura concludes that if there is a Shabbos need to remove them, that it is permitted.