Often, the first sign of trouble is an unusually large water bill. Because leaks often start small and get larger over time, compare your current water usage with last year’s bill. Unexplained increases in usage are a good indicator that you have one or more leaky or broken pipes. To be sure, make sure all of your plumbing fixtures and appliances, such as toilets, taps, washing machines and dishwashers, are not being used. Don’t forget about less obvious things such as yard sprinklers or ice makers. Then check your water meter. If the meter shows water use when you aren’t using any, you almost certainly have a leak somewhere.

In most homes, shut-off valves for each fixture or appliance are located under or behind the units. Sink valves are often found inside vanities or sink base cabinets. Shut off all the valves, then check the meter again. If the meter is not running, the problem probably lies in one of your fixtures or appliances. Contact your plumbing professional for a quick resolution. If the meter shows that water is still flowing even with all the valves shut off, you probably have a more serious plumbing problem. Your home’s pipes will likely need to be repaired or replaced.

Other signs of failing pipes include damp or stale smells that indicate the growth of mold or mildew due to moisture from leaks. Chronic leaks may leave discolored areas on walls, especially in the corners and where the walls meet ceilings or floors. Water stains often have clear edges and may show streaks of gray or black. With a gloved finger, touch suspicious stains and look for the telltale shine of moisture on the latex. Black or colored spots or patches may indicate mold or mildew growth. Often, these signs hide in places you don’t often look, such as the insides of cabinets, closets and utility rooms.