Outdoor Faucet Installation

Frost-proof means the valve is inside

The difference between a tap that survives winter and one that splits is where it closes.

A standard tap closes at the outlet, which leaves the entire barrel full of water sitting outside in the cold. That water freezes, expands, and splits either the tap or the pipe behind it.

A frost-proof sillcock has its valve seat at the inside end of a long barrel. Close it and the water stops inside the heated envelope of the building, leaving the exposed section empty.

That is the whole design, and it only works if two conditions hold.

Pitch it, and disconnect the hose

A frost-proof tap installed badly fails exactly like a standard one.

Pitch. The barrel has to slope slightly downward toward the outside so it drains itself after every use. Installed level, or worse pitched back toward the building, it holds water in the cold section and the frost protection is entirely theoretical.

The hose. A hose left connected over winter seals the outlet, so the barrel cannot drain no matter how well it was pitched. Water stays in it, freezes, and splits the tap.

Disconnecting hoses before the first freeze is the single most useful winter habit for an outside tap, and it is the reason most frost-proof taps that fail, fail.

While fitting one, an isolating valve on the inside of the wall is worth having too. It means the tap can be shut off and drained for winter without involving the rest of the house.