Abstract: The sillcock includes an inner tubular pipe forming a water-flow passage and an outer tubular pipe cooperating with the inner tubular pipe to form a water relief chamber. When the inner tubular pipe is ruptured as a result of the expansion of ice in the inter-flow passage, water from the source is directed across the open valve of the sillcock into the water-flow passage where it escapes into the water relief chamber through the ruptured opening. The relief chamber is opened to the atmosphere and water emerging therefrom alerts a person to the fact that the inner tubular pipe has ruptured thereby requiring repair or replacement.