Every time news breaks of a tragic building collapse, you may wonder how safe your own home is. It may seem sturdy, but it’s not an indestructible monolith. Every house has five major systems that work together to keep it livable and each one has its own potential problems that can lead to disaster if left unrepaired.

Look, listen, and sniff for the warning signs below to know whether you need to schedule repairs.

Signs of foundation and structure problems

Your home’s foundation is commonly made of concrete and connects the structure itself to the ground. Above that, the structure, or frame, may be made of concrete, wood, metal, or some combination of those materials. Beneath your feet is the plywood subfloor. Together, these keep your house standing, so it’s crucial to be aware of symptoms of structural issues. Keep an eye out for:

  • Visible cracks in the chimney or the house’s exterior
  • Windows and doors that stick, don’t open or close smoothly, or won’t lock
  • Doors that won’t stay closed
  • Cracks in the drywall around sticking doors or windows
  • Cracks in vinyl or tile floors
  • Long cracks or bowing in basement or crawl space walls
  • A new crack in window glass
  • Soil pulling away from exterior walls
  • Floors sloping to one side or sagging in the center
  • Baseboards separating from the wall
  • Mold where the roof meets the exterior walls

“Any problems listed here could indicate serious foundation issues putting your home at risk of collapse,” notes Joe Belcher, a code consultant at JDB Code Services Inc. in Homosassa, Florida.

These are not the only signs there could be problems with the foundation or walls, but they are fairly easy to notice. You should look further for stains under your windows, which can mean water is getting in around the frame. H2O can also get into your walls, attic, or basement thanks to rusted, leaky gutters or gaps between gutters and the roof’s edge. Unwanted water can breed mold and rot your home from the inside.

Floors can have hidden issues too. If they feel strangely bouncy or soft, have high and low places, and/or make cracking or popping sounds underfoot, they could be deteriorating—possibly due to a termite infestation or water intrusion. Whatever the cause, weak floors can collapse if left unrepaired.

If you suspect termites, look for other signs, including bubbling or cracked interior paint; small, dry mud tubes on the foundation running from the ground to the exterior finish; and multiple tiny holes in the drywall or wood. Left unchecked, these insects can damage a wood structure so severely that it fails. Hire a licensed exterminator to inspect the house and provide appropriate treatment.

Other structural issues will also require an expert assessment. Should a foundation shift or a foundation wall collapse, a structural engineer will need to inspect the damage. They can determine whether it’s safe for you to stay home during repairs and where stabilizing jacks or beams must be installed before rebuilding can occur.

Electrical issues that can cause fires

The electrical system in your house consists of a breaker box, wiring, switches, and outlets. If you notice any of the following, it may have issues that could lead to fire or electrocution.

  • Warm, vibrating, or sparking outlets and switches
  • Buzzing, crackling, or sizzling sounds when you flip a switch or stick a plug into an outlet
  • Repeated circuit breaker tripping
  • Burning or odd odors
  • Clothes dryer vents stuffed with lint

In addition to these warning signs, don’t ignore switches or outlets that suddenly stop working or only work occasionally—wiring could be loose. Flickering lights also suggest a possible wiring short.

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And pay attention if you smell an unpleasant odor akin to an overheating electrical motor. Sometimes a new appliance smells the first few times it’s used, which is OK. If that’s not the case, you could have melted wiring. Unplug nearby lamps and other appliances and sniff the outlets and switches. If the smell is coming from a specific one, shut off the power at the breaker box and call a licensed electrician to check it out. Don’t try to fix it yourself unless you’re qualified to do so. Botched electrical work can hurt you and your home. Be safe—get help from an expert.

Symptoms of plumbing problems

The pipes in your home bring in fresh water and remove wastewater to the sewage system. They may be located under your floors or in your attic. Water is good; water leaks are not. Watch out for these signs of water going where it’s not wanted.

  • Swollen or warped walls
  • Cabinets that have shifted position
  • Low water pressure in the shower or continually dripping sinks
  • A water meter that runs constantly even when all fixtures are turned off
  • Perpetually wet soil around the perimeter of the house or patio

These issues indicate your house has at least one interior water leak. “Water where it’s not supposed to be can damage the foundation or make the house susceptible to mold,” says Belcher. “While mold won’t make a house collapse, if it’s a dangerous variety, it can make a house unlivable by causing constant human illness.”

There are things you can do to prevent leaks. A bulge in a washing machine or dishwasher hose, for example, means it is ready to burst. Replace it to prevent a huge flood of water from entering the house. You can also install a water leak detector, which will alert you if a leak occurs.

Beyond leaks, there can be problems with water heaters as well. If you see melted plastic grommets, deadly gases like carbon monoxide may be entering your home. While this won’t damage the house, it could kill you. This is not something most people can fix for themselves, so call your plumber for help.

Indicators of roof troubles

Your house’s roof protects you from the elements. Whether it’s made of asphalt shingles, ceramic tile, metal, or anything else, a damaged roof will let water into your home. What’s worse is it can be hard to find the actual leak since water can run a long way from the hole to where you see damage. Look for these potential roof problems:

  • Stains on the ceiling
  • Water coming in from above
  • A sagging roof
  • Damaged shingles
  • Visible mold on exterior walls

It is important to fix roof leaks promptly, as water can spawn mold, damage ceilings, rot wood, and destroy insulation. The first step is finding the leak. Go into your attic with a flashlight and look above where the water stain is, concentrating on areas near anything that penetrates the roof, such as chimneys and plumbing vents. When you see mold or discoloration, you have found the leak.

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If this doesn’t work, spray a water hose on the roof while someone else waits inside. Soak the area above where the leak shows up inside the house and have your helper yell when they see water come through. This may take some time, so be sure to wet each area thoroughly before moving on. If this doesn’t reveal the leak, you or a professional may have to remove some shingles to track it down.

Once you’ve found the leak, push a nail through it from below and mark it on the roof with chalk for visibility. If the leak is adjacent to a chimney or vent, the flashing may also need replacement. How you ultimately fix the leak will depend on the type of material the roof is made of. You may prefer to hire a roofer to handle this repair.

Potential heating and air conditioning problems

While not all houses have heating and air conditioning systems, their failure can be costly. If you smell a gunpowder odor, it could be from a fried circuit board or fan motor in your furnace. Unrepaired, this could cause a house fire.

Be on the lookout for spots in the paint around permanent air vents, too, which could be signs of mold. As indicated above, while this won’t destroy the house, certain types of mold can make a home unsafe to live in.

Do you see a white sheen (or efflorescence) on the outside of your brick chimney? This means the chimney is wet inside. When that moisture freezes, the expanding ice can slowly wreak havoc. This can also crack or break your flue liner, allowing deadly combustion gases from your furnace, fireplace, or water heater to accumulate inside your home. Installing a chimney cap and waterproofing the chimney can solve this problem. Masons are equipped to handle this work.

If you have a wood-burning fireplace or stove, creosote can build up in your chimney. Too much of it can start a house fire. You can prevent this by having a professional chimney sweep inspect your chimney annually, cleaning it as needed. They will also determine whether birds have nested in your chimney or if it is blocked by other debris. 

See the signs? Get help

If there are multiple problems or if the foundation is the issue, you might benefit from a whole house inspection.

To find an inspector, ask friends for referrals, check online referral services or contact your local government. “The inspectors at your local building department may be available or may provide a list of reputable home inspectors,” Belcher says. “In addition, if there are signs of an imminent collapse, the local building department should be consulted regarding whether the building should be evacuated, and, if so, to post the building as unsafe.”

Some private inspectors have demonstrated their knowledge by passing the written National Home Inspector Examination, which is required for home inspectors in 34 states. To see if yours is one of them, check the exam’s official website.

Professional organizations including the American Society of Home Inspectors, the International Association of Certified Home Inspectors, and the National Academy of Building Inspection Engineers also have lists of inspectors.

Expect the inspector to spend two to four hours at your home. They should provide a detailed written report of their findings with recommendations for needed repairs. If something is wrong, fix it so you know your house is safe. You can get another house, but you can’t get another you.