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
Links go to Amazon search results — buy the part that matches your specific model. Uncle AI earns a small commission on purchases, at no extra cost to you.
- Toilet flapper kit Shop →
- Fill valve replacement Shop →
- Adjustable pliers Shop →
- Sponge and bucket Shop →
Step-by-step fix
-
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.
-
2
Turn off the water supply
Turn the shutoff valve behind the toilet clockwise. Flush once to empty the tank.
-
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.
-
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.
-
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 Seattle, tap water is very soft (20–50 ppm). Seattle's water is among the softest in the U.S., sourced from Cascade Mountain snowmelt. Mineral buildup is virtually non-existent. Soft water can cause corrosion in older copper piping. Many homes use well water in surrounding areas, which can have iron and sediment.
Plumbers in Seattle typically charge $120–190/hr. Most homeowners budget $800–2,500 for common repairs like fixture replacement, drain clearing, or valve repairs.
Washington requires state licensing. Homeowner exemptions exist for owner-occupied single-family homes. Seattle requires permits and inspections.
Majority post-1960s construction. Copper is standard. Many homes have PEX. Soft water means corrosion is less of a concern than hard water metros. However, old copper piping may have pin-holing. Basement water intrusion is common due to high rainfall. Many homes have sump pumps.
Freeze risk in Seattle is minimal — hard freezes are rare. Pipe insulation is generally not a concern, though occasional cold snaps can surprise under-prepared homes.
DIY in Seattle: Seattle's moderate licensing and environmental focus create a fairly DIY-friendly environment for homeowners. Many people handle minor plumbing and electrical work. Moisture management, mold prevention, and basement waterproofing are common DIY focuses.
- 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 Seattle.
Start free diagnosis →