I have an outside water faucet that needs to be replaced. The handle and shaft assembly has damaged threading and will not mate properly with the faucet body. Therefore, I am considering replaing the entire faucet.I have a slab house and can not tell how the faucet body mates with the water pipe that comes out of the wall. Are all of these types of faucets have a threaded type of mating with the water pipe, or is the faucet body welded to the pipe? Also, any speacial precautions that I should take? What if the water pipe is pvc? Thanks much!