October is the month for things that go bump in the night. Most of the time, though, the bump has a very ordinary explanation. As nights get cooler and the heat starts running, houses tend to get a little more talkative.
Before tracking down a sound, pay attention to the details. Note when it happens, where it seems to come from, and what else was going on at the time, like the heat turning on or a faucet shutting off. Those observations will help you understand the sound, and they'll be useful if you decide to call someone. No ghost-hunting equipment required.
Why Homes Creak and Pop
Wood, drywall, metal fasteners, and other building materials expand and contract with changes in temperature and moisture. As they shift slightly against each other, they can creak, tick, or pop.
Fall makes this more noticeable. A house warms during a sunny afternoon, then cools as the temperature drops overnight. Roof framing and siding may pop as they contract, and floors can creak more as indoor air gets drier during heating season. The house is also quieter at night, which makes every small sound easier to hear.
Occasional creaks are part of how most homes behave. New cracks in walls or ceilings, doors that suddenly stick, or floors that feel soft or bouncy are worth having a professional look at.
What's Making Noise in the Pipes?
A loud knock or bang right after a faucet or appliance shuts off is often called water hammer. Water moving through the pipe stops abruptly when a valve closes, and the pressure shift can make pipes thump or shake. Washing machines and dishwashers, with their quick-closing valves, are frequent sources. A plumber can check water pressure and pipe supports and suggest ways to reduce it.
Ticking as hot water runs usually comes from pipes expanding as they warm and rubbing against framing or straps. It tends to stop once the pipe reaches temperature.
The sound of running water when nothing is on deserves attention. A toilet that refills on its own every so often may have a worn flapper. If you can't find the source, check your water meter with everything turned off. Movement on the meter could point to a leak, and that's a good time to call a plumber.
The Sounds of Heating Systems and Appliances
Heating equipment makes a range of normal sounds. Furnaces often click as they ignite, hum while running, and whoosh as the blower moves air. Metal ductwork may pop or tick as it heats and cools. Boilers and radiators can gurgle or knock when air is trapped in the system. Heat pumps may make a whooshing or hissing sound when they switch into defrost mode on cold days.
Refrigerators, water heaters, and other appliances have their own routines of buzzing, humming, and clicking as they cycle on and off.
What matters most is change. New grinding, squealing, rattling, or loud banging when the system starts is worth a call to a heating technician. If you ever smell gas, leave the home and call your gas utility or emergency services from outside. If a carbon monoxide alarm sounds, get everyone outside and call for help.
When Wind Makes the House Whistle or Rattle
On a windy fall evening, a house can produce sounds surprisingly out of proportion to their cause. Air forced through a small gap around a window, door, or attic hatch can create a high whistle. Weatherstripping that has worn or shifted is a common culprit.
Rattling and tapping often come from exterior parts moving in the wind. Dryer vent flaps, bathroom exhaust dampers, loose gutters, and branches brushing the roof or siding are frequent sources. A look outside the next day, near where the sound seemed to come from, often solves the mystery. If the cause is on the roof or out of reach, leave it to a professional.
Scratching and Scurrying Behind the Walls
Scratching, scurrying, or gnawing that repeats in the same area can point to mice, squirrels, or other animals that have found a way inside as the weather cools. Timing can offer a clue. Mice are often more active at night, while squirrels tend to move around during the day.
Look for other signs, such as droppings, chewed materials, or small openings around the foundation, roofline, or where utility lines enter the house. If the sounds keep coming back, a pest control or wildlife service can identify what's there and how it's getting in. Some areas have specific rules about removing wildlife, which a licensed professional will know.
What to Tell the Professional
If you do call someone, the notes you gathered at the start become useful. Describe what the sound is like, where you hear it, when it happens, and what else is going on at the time. Mention how long it's been happening and if it has changed. A short recording on your phone can help too.
"The pipes bang every time the washing machine finishes filling" gives a plumber much more to work with than "the pipes are loud."
