Every business has its routine, petty annoyances. For doctors, I'd guess it's the old digital prostate exam. For lawyers, it's probably knowing that defendants in previous lawsuits are out there plotting the sort of revenge that the Glenn Close character in Fatal Attraction would find harsh. In the home-inspection business, it's stuff that breaks soon after it gets inspected.
Once or twice a year, somebody will call me and tell me that something I said was just fine has quit working, and furthermore, I should've known it was going to quit working. I do my best to listen patiently, and I try to offer solutions to the problem. But truth be told, while I'm listening, I'm thinking to myself, Get a grip. Everything quits working sooner or later; this thing just quit working soon after I looked at it. Of course, I don't say that. I just listen to the fussing and fuming, and say, "Thank you for your generous input."
Right now, though, while nobody's yelling in my ear, I'm going to do my very best to tell you about some things that will break at your house, when the unfortunate events will happen, how predictable they are, and what you can do to prevent trouble:
Your roof will leak. Shingles are under constant attack from wind, rain, sun, heat, and cold. Most modern flashings are poorly installed. Sooner or later, there will be a hole in your roof, and water will find it.
When: Typical asphalt/fiberglass shingles last about 12 to 15 years, although leaks can develop at any time.
Predictability: Low. If you examine the roof once or twice a year, you might see trouble in the making (loose or worn shingles, loose flashings).
Preventability: Low. You can do routine maintenance, but you can't control the weather.
The ground-fault circuit interruptors (GFCIs) in your electrical system will fail. GFCIs are important safety devices, but they're mass-produced, cheaply made things. They wear out. Also, electricians are prone to wiring them improperly.
When: They might not work the day they're installed.
Predictability/Preventability: None, but bad GFCIs are easy to discover. You can test them with a $10 GFCI tester, available at any decent hardware store. If you find a bad one, replace it.
Your plumbing will leak, clog up, and wear out. For cryin' out loud, everybody understands the power of water, don't they? Water made the Grand Canyon. Water heater tanks will fail; plumbing joints will blow; commodes, faucets, and showers will drip and leak; and old galvanized and cast-iron pipes will clog up.
When: Hell, there's always something wrong with the plumbing.
Predictability of leaks: Very low. Sometimes you can spot a seeping leak before it starts to drip, and a dripping leak before it starts to pour. But you can't look at a perfectly good pipe and say, "That one will blow next Thursday."
Predictability of clogs: Zero. Think of it this way: If cardiologists, with all their fancy tests and scanners, can't predict when a critical artery will clog up, what can you expect from plumbers or home inspectors?
Preventability: Zero on the leaks, not applicable to the clogs. If you've got old galvanized supply pipes or cast-iron drains, you can be sure they'll clog up sooner or later. But who spends money on plumbing before something goes wrong?
As a result of a leak, something will rot. The leak could come from your kitchen faucet, your commode, or your shower floor. I once found a 20-year-old leak in a wall caused by an errant siding nail. Anyhow, there's almost always something leaking. If wood gets wet and stays wet, it will rot. Rot can grow slowly or quickly. Nobody can look at rot and tell how old it is.
Preventability: Varies. If you catch the leak soon enough, no harm done.
Your heat-and-air system will die. Heat-and-air equipment contains delicate electronic parts, plumbing, and motors. The heat exchanger and A/C coils are exposed to extreme temperatures. It's a tribute to American know-how that heat-and-air equipment works at all. Common sense says the equipment will break down, probably several times before it wears out.
When: An individual part (such as a blower motor or a thermocouple) could quit working at any time. As far as the whole system is concerned, it'll probably last about as long as a good dog if you take care of it. That means changing the filters at least once a month and having the system serviced twice a year. If you mistreat the system, it will last about as long as a pet rat.
Predictability: Virtually zero. Most of the time, you could have a team of heat-and-air engineers out to your house the day before your system dies, and it would check out fine.
Preventability: Excellent. Keep up with routine maintenance and service.
Finally, let me offer this: The next time a tradesman or a handyman comes to your house to fix something, and he tells you that the last guy who looked at the broken thing should have seen the breakdown coming, ask him to put that in writing. I can predict the outcome of that scene with 100-percent accuracy: He'll backtrack, he'll cover, he'll fudge-but he won't put it in writing.