How often should you check your toilets for silent leaks?

Why bother

A silent leak quietly runs up the water bill. Standard upkeep. Dull and cheap, and a lot less dull than whatever it's quietly preventing.

What the job involves

1. Lift the tank lid off and rest it flat somewhere it won't get knocked. Drop a few drops of food coloring, or a leak-detection dye tablet, into the tank water and leave the flush alone.
2. Wait about 10 to 15 minutes, then look in the bowl. Colored water means the flapper or seal is leaking. Clean water means you're fine, lid back on, you're done.
3. If it's leaking, the usual culprit is the flapper, the rubber valve at the bottom of the tank. Shut the supply valve, flush to empty the tank, unhook the old flapper and clip on a matching one. About $5 to $30 and a quarter of an hour.
4. If it still leaks, or the tank keeps overfilling past the marked waterline, the fill valve is the next suspect. Swap or adjust that and you've worked through the two things that go.

Do it yourself, or pay someone?

Yourself. The dye test costs nothing, a flapper is $5 to $30, a fill valve $8 to $30, and either is a 15 to 30 minute job with no special tools. Hiring it out is mostly labor, roughly $60 to $150 installed, or Angi's $100 to $400 for a running toilet. Only call a plumber if the leak's at the tank-to-bowl bolts or the supply line won't shut off.

What skipping it costs

$60 to $360 a year, and that's the water bill, not a repair. A worn flapper lets water seep from tank to bowl around the clock, so the meter keeps turning while you hear nothing. The EPA reckons the average household's leaks waste more than 9,300 gallons a year, which at typical water-and-sewer rates is on the order of $50 to $90. A steadier leak, the kind cost guides peg near 200 gallons a day, runs about $30 a month, so roughly $360. Heavier ones cost more still, and the figure swings with your local rates. A few drops of food coloring tells you which end you're at.

Signs it's overdue

• The water bill creeps up with no change in how much anyone's using the house. The EPA calls that the tell-tale sign of a hidden leak.
• A faint hiss or trickle, or the toilet topping itself up out of nowhere when no one's touched it, the so-called phantom flush.
• A thin stream or ripples running down the inside of the bowl between flushes, or a dye test that tints the bowl water.

When to start thinking about it

A few days' warning does it. Grumpty grumbles 2 days out, then leaves you alone. Mark it done and Grumpty sets the next one, every 12 months, so you can go back to forgetting it exists.

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