What will wreak havoc with your flooring and ruin your shoes when you find it?
A cracked toilet tank, which, according to Joel Gwartz of B.J. Discount Plumbing & Heating Supplies in Garden Grove, "happens to just about everyone at least once."
It's one of those plumbing catastrophes that usually occurs when you least expect it and when you're least prepared.
However, if you have a few of the right tools and can think fast on your feet, you can avoid an expensive after-hours call from a plumber.
* Cracked toilet tank. If the sound of a continually running toilet arouses your suspicions and you find the bathroom floor has become a lake, you could be a victim of the cracked tank.
This usually affects older toilets, where the stress of water pressure on the porcelain creates a small crack, which widens to the point where water flows out freely.
If you find it while you're home, count yourself lucky. Imagine what your house would look like with water soaking the floors during the two weeks you're on vacation.
If it happens to you, turn off the water connection to the toilet, which can be harder than it sounds.
"In many cases the shut-off valves for toilets and sinks haven't been used in years and are locked," says Gwartz. "I'd recommend that at least once a year, you should turn those valves off and on again just to make sure they're working properly."
Keep epoxy putty around the house, which can be used to make emergency repairs on toilet tanks and water lines.
"It basically comes as two sticks of putty and you break off the amount you need and squish them together," says Ed Howard, a plumber from Fullerton. "Once they begin to heat up through the chemical reaction, you press it into the areas you want to seal, and give it at least a day to cure."
* Broken water line. Similar to the cracked toilet tank, an old line can develop a leak that eventually expands into a gusher, or an exposed line can be smacked by a ladder or shoved by a heavy box under the sink and split.
In addition to knowing where the local shut-off valves are, you should also know where the valve that controls water entering the house is, and make sure it isn't frozen. This is essential when water is coming from a line for which you can't find a valve.
"I also think you should have a meter key, which you can use to turn off the supply at the water meter," says Gwartz. "Most hardware stores carry them, and it's probably important that everyone in the house knows where it is and how to use it."
To make an emergency fix, you can use epoxy putty or a repair coupling available at plumbing supply stores. You wrap the rubber tubing around the broken pipe, then attach the hinged metal coupling and screw it down tight.
If you don't have a coupling on the workbench, you can create a makeshift one with a piece of rubber tubing that will fit around the pipe and a few radiator hose clamps.
* Broken water heater. You know it's going to be a bad day when you turn on the shower in the morning and find the water's cold. With gas heaters, the pilot light has usually gone out.
If you smell a strong gas odor, call your gas company. If the odor's slight and you suspect a doused pilot light, follow directions in the owner's manual or on the bottom door to the heater on how to relight it.
If the water heater is stored in a closet inside your house, it's often forgotten until something goes wrong. But a small water leak from the water heater can grow and damage your floors. Take a look at the water heater every couple of months to check for leaking, especially around the drain valve at the bottom.
"Many of the newer water heaters have plastic drain valves that tend to last only about three to five years before developing a leak," says Larry Hohenstein of Amco Building & Plumbing Supply in Costa Mesa. "I always suggest removing it when buying a new water heater and installing a standard hose bib with a cap."
*Plugged drain. That miserable fact that drains and toilets tend to back up just before Thanksgiving dinner or during a party is probably because the plumbing is under heavy use rather than a reflection of your luck.
For an unexpected stopped-up sink, nothing beats the effectiveness of an old fashioned plunger, provided it's used correctly.
"I see people work with a plunger for an hour or more on a sink and they've gotten nowhere," says Howard.
"Make sure, if you're working on a bathroom sink, that the overflow holes are plugged with a wet cloth. It's best if you have someone stand there and hold it tight against the holes. Otherwise, you're not creating enough of a vacuum for the plunger to work."
For toilets, use a toilet auger, snake or a toilet plunger. If these don't work, there could be a problem in the venting of the drain.
"If something clogs the vents on the roof, it's going to affect how well your toilet flushes," says Hohenstein. "If you haven't had it done in a few years, I'd advise having someone go up on the roof and run a snake down the vents to clear any obstructions. You'd probably be surprised at the results."
If all else fails, you can use electric augers, which are available at rental yards, are easy to use and will work for about half the price of a professional's house call.
However, if you just feel like giving up and flipping through the Yellow Pages, don't feel too bad.
"I think the best thing people can have around the house for plumbing emergencies is a plumber," says Gwartz.