When to Replace Your Sillcock

Sillcocks (outdoor faucets, also called hose bibs) last 15 to 25 years. A frost-free sillcock is a specific design where the valve seat and washer are located 6 to 12 inches inside the wall, in the heated space of the house, rather than at the exterior handle. This design prevents freezing because the water shuts off inside the warm zone, and the short section of pipe between the valve and the exterior drains out by gravity when the faucet is closed. Standard (non-frost-free) sillcocks have the valve right at the exterior wall and are extremely vulnerable to freeze damage in cold climates. If you live anywhere that gets below 32°F and your outdoor faucet doesn't have a long stem (8-12 inches from handle to the back of the unit), it's a standard sillcock and you need to shut off and drain it every winter or risk a burst pipe inside the wall. The most common failure is freeze damage... even frost-free sillcocks can freeze if a garden hose is left connected in winter. The hose traps water in the pipe that can't drain out, and when that water freezes, it expands and cracks the pipe or valve body. The crack may not leak immediately. Many people discover the damage in spring when they turn on the outdoor faucet and water pours inside the wall. Other failures include a worn washer (causing a drip from the spout), a failed packing nut seal (causing a drip from around the handle), and corrosion of the valve body from years of exposure to weather and hard water.

Replacing a sillcock takes 1 to 2 hours for a DIYer, longer if you need to open up interior wall space.

Steps: shut off the water supply to the sillcock (there should be an interior shutoff valve on the supply line... if there isn't, shut off the main). Open the outdoor faucet to drain residual water. From inside, cut the supply pipe behind the old sillcock. From outside, remove the 2 screws holding the sillcock to the exterior wall and pull the unit out through the wall.

Measure the wall thickness to determine the correct length for the new sillcock. The valve end should extend at least 1 inch past the interior wall surface. Frost-free sillcocks come in 6, 8, 10, 12, and 14-inch lengths. If between sizes, go longer and adjust the pipe connection inside.

Insert the new sillcock through the wall from outside. Secure it to the exterior wall with screws. From inside, connect the supply pipe to the new sillcock using either solder (copper-to-copper), a SharkBite push fitting (the easiest option for copper or PEX), or a compression fitting. Make sure the sillcock slopes slightly downward toward the outside so water drains out when the valve is closed... this is what makes the frost-free design work.

Apply exterior caulk around the sillcock where it passes through the wall to seal against water and air infiltration. Turn on the water, check for leaks inside and outside, and test the faucet operation.