Most homeowners in Minnesota know it's important to 'winterize' the outside faucets to prevent them from freezing, because freeze damage can destroy the faucet or lead to a burst pipe. The problem is that many people don't quite get it right; winterizing the outside faucets in the fall seems like a simple thing to do, and it seems like it should be straightforward and easy, but there are a few tricks you need to know to really get it right.
Garden hoses - First and foremost, disconnect the garden hose from the outside faucet. If you leave your garden hose attached to the faucet, you're asking for trouble.
Determine if your faucet is frost-free or not. A rule of thumb is that if the faucet has a knob that's perpendicular to the house, it's frost-free. The knob turns a long stem that closes a valve inside the house where it's warm. If the knob is at a 45 degree angle, it's not frost free, and it needs to be winterized. This is only a rule of thumb though; if a boiler drain is installed at the exterior of the home, it will have a knob that's perpendicular to the house, just like a frost free faucet, but it won't be frost free. The photo below shows an example of a boiler drain installed at the exterior of a house.
To know for sure whether a faucet is frost-free or not, look up inside the spout. On a frost-free faucet, all you'll be able to see is a metal stem. On a faucet that isn't frost free, you'll be able to see the valve components open and close when the handle is turned. The images below show a faucet that is not frost-free.
Frost-free sillcocks with an integral vacuum breaker A properly installed frost-free sillcock with an integral vacuum breaker can have the water left on year 'round without any problems. A properly installed frost-free sillcock will have a slight downward pitch; this allows water to drain out when the faucet is shut off.
When frost-free sillcocks aren't installed with this downward pitch, water will sit inside the stem of the sillcock even when it's turned off. The pitch is a little dramatic in the photo below, but you get the point.
If this water freezes, it can burst the stem of the sillcock. Most homeowners don't know this has happened until the first time they use their faucet in the spring. Once they turn their faucet on, water starts shooting out of the burst stem inside the house, making a big mess while nobody is inside the house to see it. This happened to Connecticut home inspector James Quarello while he was inspecting a home a couple of years ago. Better him than me, I say.
The fix for an improperly installed frost-free sillcock is to have it re-installed with a slight downward pitch.
Winterizing standard sillcocks With a standard sillcock, the water needs to be turned off and drained out to prevent freeze damage. To do this, you'll need to first turn off the water supply to the faucet from inside the house. Exterior faucets should have a separate shutoff valve inside the house, but not all of them do. On older homes, these valves are typically located at the ceiling somewhere close to the outside faucet. On newer homes, the valves are typically located right next to the main water valve, and they're also usually labeled.
Once the water is turned off inside the house, the outside faucet needs to be opened up. Next, the bleeder cap inside the house needs to be unscrewed - this will allow water to drain out of the pipes. Depending on how the pipe is pitched, the water may drain through the bleeder cap or through the outside faucet. Keep a small bucket handy when you do this, just in case a lot of water needs to drain out of the bleeder. After the water drains out, you can screw the bleeder cap back on and turn off the outside faucet.
Sometimes, two wrongs really do make a right Some older houses in Minneapolis and Saint Paul don't have a shutoff valve for the outside faucet, and the faucets never get winterized... yet they never have a problem with freezing. How can this be? Here's a hint:
On older houses with no insulation at the rim space, there can be so much heat loss occurring here that the outside faucets never get cold enough to freeze. I call this two wrongs making a right. It's certainly not a reliable method of preventing freeze damage, but it does seem to work.
Vacuum breakers complicate things The problem with external vacuum breakers (aka backflow preventers) is that they don't allow all of the water to drain out. After the water is turned off and appears to have drained out, the rubber seal in the vacuum breaker will still trap enough water to destroy the vacuum breaker, which will cause water to spray out all over the place when the faucet is used again in the spring.
There are two possible solutions: remove the vacuum breaker in the fall, or drain the water out of the vacuum breaker. If the vacuum breaker will just unscrew from the sillcock, go ahead and take it off in the fall. The problem with this is that vacuum breakers are often designed to be permanently installed. They have a little set-screw on the side that gets tightened down until it breaks off, making it so the vacuum breaker can't be removed. If your vacuum breaker leaks every time you turn on your faucet and you need to replace it, there is still a way to remove it without destroying your faucet - I made a video showing how to do it.
If the vacuum breaker can't be removed or you don't want to hassle with removing it, no problem; there is still a way to drain the rest of the water out. If you look up inside the vacuum breaker, you'll notice that there is a small white plastic post. Just push this post to the side, and the rest of the water will drain out. The video below shows how this works.
If the vacuum breaker doesn't have that white post, it may have a plastic ring that will allow it to drain. What about those insulated faucet covers? I don't trust 'em. They're probably just a little better than nothing. Don't waste your time.
Author: Reuben Saltzman, Structure Tech Home Inspections