Two years ago we had an early hard freeze. I had turned off the outside water on schedule, but forgot to disconnect the garden hose from the 'freeze-proof' sillcock. They're not 'freeze-proof' when you do that. The ice split the main pipe right inside the house. I didn't see the split which was up in the basement ceiling, so we had a minor flood in the basement when I turned on the outside water in the spring. Plumber told me that he had replaced 9 other sillcocks that week alone. By my calculations based on his fee, I figure he just paid for a semester of college for his kid.