What's actually causing this
Toilets run when water continuously trickles from the tank into the bowl. The two most common culprits are a worn-out flapper that doesn't seal properly, and a fill valve that's stuck open or set too high.
What you'll need
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- Toilet flapper kit Shop →
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Step-by-step fix
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1
Diagnose the problem
Lift the tank lid and add a few drops of food coloring. If color appears in the bowl within 10 minutes without flushing, the flapper is leaking.
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2
Turn off the water supply
Turn the shutoff valve behind the toilet clockwise. Flush once to empty the tank.
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3
Replace the flapper
Unhook the old flapper from the overflow tube pegs. Snap the new flapper in place and reconnect the chain — leave about half an inch of slack.
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4
Adjust the fill valve
If water is running over the overflow tube, the water level is too high. Adjust the float arm or float ball downward until the water sits 1 inch below the top of the overflow tube.
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5
Turn water back on and test
Slowly open the shutoff valve. Let the tank fill and listen for any continued running after the fill cycle completes.
In Houston, tap water is very hard (300–380 ppm). Houston's water is very hard. Calcium and magnesium deposits are visible within months on fixtures. Water heaters fail faster than national average. Water softeners are common among maintenance-conscious homeowners.
Plumbers in Houston typically charge $80–130/hr. Most homeowners budget $800–2,500 for common repairs like fixture replacement, drain clearing, or valve repairs.
Texas has minimal state licensing for plumbers. Local jurisdictions (Houston) require permits for water line work. Homeowners can do most plumbing work if they obtain permits. No master plumber requirement.
Majority post-1960s construction. Copper and PVC are standard. Slab-on-grade construction is prevalent; leaks under the slab are expensive to repair. Clay soils cause differential settling, which can stress plumbing. Hard water means water heaters typically need replacement every 8–10 years.
Freeze risk in Houston is minimal — hard freezes are rare. Pipe insulation is generally not a concern, though occasional cold snaps can surprise under-prepared homes.
DIY in Houston: Texas's permissive licensing and DIY culture make Houston one of the most DIY-friendly major metros. Homeowners regularly tackle plumbing, electrical, and HVAC work. Permits are cheap and inspections are straightforward. Hard water management is a common DIY focus.
- The tank or bowl has visible cracks.
- The toilet rocks or is loose at the base — this may indicate a wax ring failure.
- Water appears on the floor around the base after flushing.
Let Uncle AI diagnose it first.
Describe the problem. Uncle AI asks the right questions and tells you exactly what's broken — and whether you should fix it yourself or call someone in Houston.
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