Flickering lights. A slamming door. The scent of perfume wafting through the air. Some might claim that these unexplained noises and happenings indicate paranormal activity in your home. But there’s likely a far less haunting explanation.

Cold Spots

Drafts could be the result of a restless apparition, but they’re more likely caused by air leaks or inadequate insulation. Professional energy auditors often use infrared instruments to identify such cold spots, but Consumer Reports has found that a simple incense stick can do the trick.

If smoke from the stick blows sideways when you hold it up to windows, doors, and walls, air is seeping in and out from those areas.

Depending on the location, placing caulk around window and door frames, weatherstripping around doors, or insulation for larger gaps should eliminate the cold spot, says CR test engineer Enrique de Paz. "If the leak is around a window sash, though, those fixes aren't applicable," he says. In this case, you could install an interior window sealer—the plastic sheets that seal off the window. "Or, if the leak is coming from a small area, I've found that applying a 2-inch-wide painters tape across the spot seals it really well," says de Paz, who has tested windows at CR for nearly two decades. 

Ridding your house of drafts will keep you comfortable this winter—and could significantly lower your heating bills.

Appliances That Turn On and Off

Here’s a case where the scientific explanation is scarier than the paranormal one. In recent years, Consumer Reports has noted many instances of appliances turning on by themselves or spontaneously combusting, posing serious safety risks to homeowners. Last fall, we reported on cases of “exploding” Samsung top-loading washers that seemingly self-destructed on high spin speeds.

Back in 2010, Electrolux recalled 122,000 smoothtop ranges and cooktops after liquid pooling under the control knobs caused 70 units to turn on unexpectedly.

With larger appliances, report any phantom activity right away to saferproducts.gov, as well as to Consumer Reports through our Report a Safety Problem page.

Lights and electronics can also turn on and off without cause. If storms are passing through, this could be due to a whole-house power surge. Otherwise, the activity is probably related to a defective switch or loose circuit connection. Both pose a serious fire hazard, so have the problem checked out immediately by a licensed electrician.

Things That Go Bump in the Night

It could be a flying witch, but a squirrel is more likely. In addition to making a racket in the attic, squirrels and other rodents can wreak havoc on insulation, which in turn drives up your energy costs. Haunting a home’s lower levels, small rodents like to hang out in large electrical appliances, where their wire-chewing can cause fire hazards or expensive repairs. The best way to control pests is to block their entry by plugging holes in your home’s exterior, including foundation walls and roof soffits.

Your home’s heating system can be another source of knocks and pings, many of which are perfectly normal, says CR test engineer Bernie Deitrick. "Almost every heating system involves heat and metal in some way," he explains. "And the thermal expansion of metal will often result in noises." Electric baseboard heaters, the pipes for hot water and steam heat, and the ductwork in forced-air systems click and clank as they heat up and cool down.

Plumbing lines are another source of knocking, due to pressure changes in the pipes. If the hammering becomes too nerve-wracking, a qualified plumber should be able to dampen it by installing a pressure regulator. Or, try a water hammer arrester.

Doors and Cabinets Opening

There’s something in the air with this one—low relative humidity. Drier air causes wood to shrink, which in turn can make doors, drawers, and cabinets open on their own. Leaving the bathroom door ajar when you shower in the winter is one way to raise humidity levels in your home. You can also invest in a humidifier. You'll find humidifiers for small, medium, and large rooms in CR's humidifier ratings.

Cabinet drawers with slides that have cheap nylon wheels, as opposed to ball-bearing assemblies, might also open suddenly. See our cabinet buying guide for more information on quality construction.

Mysterious Scents

The perfume of a former habitant who died on her wedding night? The muddy boots of a Civil War soldier who once quartered in the back room? Maybe. But before you call an exorcist, look for other sources of unexplained smells in your home.

Wet fiberglass hidden behind walls can give off a musty odor. Dead rodents are also none too sweet-smelling. The perfume cards that come with magazines could be to blame for the intermittent aroma. Or perhaps you recently started using a new fabric softener or detergent. Many laundry products can pack a powerful fragrance.