The riskiest plumbing week of the year for an empty house is a holiday week. If you are leaving Pittsburgh for Thanksgiving and a cold snap arrives while you are gone, a frozen pipe can split and run water into your home for days before anyone notices. The good news: an hour of shut-off, draining and thermostat steps before you leave makes that scenario very unlikely.

Why an Empty House Is at Higher Risk

When you are home, you catch the early warnings — a faucet that slows to a trickle, a cold room, a strange noise in the wall. You also run water all day, which keeps it moving and brings warmer water up from the main. An empty house gets none of that. Water sits still in the coldest pipes, the thermostat is often turned down to save money, and nobody is there to shut the water off in the first ten minutes when a pipe lets go. Most holiday flood damage is not caused by the freeze itself, but by the days a split pipe flows unchecked. Your pre-trip routine is about making sure that even a worst-case freeze cannot become a worst-case flood.

Step 1: Decide — Shut Off and Drain, or Leave the Water On?

For trips of several days or more during freezing weather, the safest option is to shut off the main valve and drain the lines. For a short overnight or two-day trip in mild weather, leaving the water on with the heat up and a faucet dripping is usually reasonable. If the forecast shows nights dropping into the 20s while you are away, choose the shut-off-and-drain route. If you have never located your main valve, find it before this trip — our guide to finding your main water shut-off valve shows the usual Pittsburgh locations, and a valve you cannot find in an emergency is a valve you effectively do not have.

Step 2: Drain the Lines After Shutting Off

With the main valve closed, open the lowest faucet in the house — often a basement laundry sink — and then open faucets throughout the home to let air in and water out. Flush each toilet once to empty its tank. Leave the faucets open while you are away so any remaining water has room to expand if it freezes. If you will be gone a long time, draining a few gallons from the water heater relieves pressure too; at minimum, set the heater to its vacation or pilot setting so it is not trying to keep a full tank hot in an empty house. Make a short note of everything you shut off, so your return routine reverses it in order.

Step 3: Set the Thermostat for the Pipes, Not the Furniture

Keep the heat on while you are away. It is tempting to switch it off entirely, but the heating system is what keeps your wall cavities and basement above freezing. Set the thermostat no lower than the mid-50s, and higher if your home has known cold spots such as pipes in an outside wall or above an unheated garage. Open interior doors and the cabinet doors under sinks on exterior walls, so the warm air you are paying for actually reaches the pipes.

Step 4: Take Care of the Outdoor Lines

Before any winter trip, outside faucets should already be winterized — hoses disconnected and the lines drained where interior shut-offs exist. If you skipped it this fall, do it now: our outdoor faucet winterizing guide takes about fifteen minutes per faucet. A hose left connected is one of the most common causes of a split pipe that only gets discovered in spring.

Step 5: Line Up a Human Backup

Ask a neighbor or friend to walk through the house every couple of days, or at least after any night that drops well below freezing. Leave them a key, the location of your main shut-off valve, and your phone number. A five-minute check after a cold snap catches a small leak while it is still small. If your trip is a long one, include the sump pump in the check — make sure it is plugged in and its basin is clear, since a pump that cannot run during a thaw or a winter storm leaves the basement unprotected.

Staying Home and Hosting Instead?

Your risk profile is the opposite: too many guests, too much grease, and a garbage disposal working overtime. Our Thanksgiving plumbing prep guide for hosts covers the kitchen and guest bathroom steps that keep a house full of people from turning into a holiday service call.

When You Get Home

Reverse your routine slowly. Close the faucets you left open, then open the main valve gradually and walk the house while the lines refill, checking under sinks, around the water heater and in the basement for drips. Run each faucet briefly to clear the air. If you spot a leak at this stage, close the main again — a pipe that split while you were away often only reveals itself when pressure returns, and catching it in the first minute is exactly what this routine is for. Our overview of what burst pipe repair involves explains the next steps if you do find damage.

Frequently Asked Questions

Should I shut off the water when I leave for Thanksgiving?

If you will be gone several days and freezing nights are possible, yes — shutting off the main and draining the lines is the safest option. For a short trip in mild weather, leaving the water on with the heat set in the mid-50s or higher and a faucet dripping is a reasonable alternative.

How low can I set my thermostat while I’m away?

Keep it no lower than the mid-50s, and higher if your home has pipes in outside walls, garages or crawl spaces. Turning the heat off completely is one of the most common causes of frozen pipes in empty homes.

Do I need to drain my water heater?

A full drain is not necessary for a holiday trip. Set the heater to its vacation or pilot setting; if you shut off the main water supply, the heater should not be left trying to heat normally. Draining a few gallons is optional pressure relief for longer trips.

What if a pipe bursts while I’m away?

If your main valve is shut off, the damage is limited to the water already in the lines — which is exactly why the shut-off matters. If a neighbor finds a leak, they should close the main valve first, then call you and a plumber.

One hour before you leave — shut off, drain, set the thermostat, open the cabinets, hand a neighbor the key — buys you a Thanksgiving trip where the house takes care of itself. Come home, refill the lines slowly, and check the usual spots. And if you return to a drip you cannot explain, or a pipe that did not survive the cold snap, Man Made Services helps Pittsburgh homeowners with frozen and burst pipes all winter — we will get the water stopped and the line repaired.