Toilets, tank to floor
Toilet Repair & Replacement Denver
Running Toilets, Rocking Bowls & New Installs
A toilet fails quietly. It runs at three in the morning, rocks a quarter inch when you sit down, or sweats onto the floor all summer. None of it feels urgent until the subfloor turns soft. Here's how each symptom actually gets fixed.
- Fill valve vs. flapper
- Rocking bowls and flanges
- Rough-in sizes that matter
- The repair-or-replace math
The toilet that runs all night
Two parts do all the work inside a tank, and both are cheap. The flapper seals the flush valve opening at the bottom. The fill valve refills the tank and shuts off at a set level. A toilet that runs is telling you one of them quit, and a dye test sorts it out in ten minutes: squirt food coloring into the tank, leave the handle alone for a quarter hour, and any color that bleeds into the bowl convicts the flapper.
Chlorine tablets in the tank are the most reliable way to destroy a flapper ever invented. They eat rubber and they eat the seal on the flush valve seat, often in a single season. Homes on softened water in Weld and Adams County tend to see flappers go slick and glazed. Homes on soft Denver supply mostly see them get old and stiff.
A fill valve that whines, chatters, or refills in short bursts is usually reacting to grit or to pressure that's running high. Front Range pressure varies wildly by zone, and in a steep town like Golden, two neighborhoods a few blocks apart can live in different worlds. If fixtures all over the house are noisy and hoses fail early, a pressure gauge on an outdoor hose bib costs about ten dollars and settles the argument.
Fix the running toilet first. It's the cheapest water bill you'll ever lower.
- If dye reaches the bowl without a flushthe flapper or the flush valve seat is leaking. Replace it, and skip the tank tablets afterward.
- If the tank refills in short bursts on its ownthe same seal is passing slowly. Check the water level against the overflow tube while you're in there.
- If water runs into the overflow tube constantlythe fill valve isn't shutting off or is set too high. Adjust it first, replace it if it ignores you.
- If the bowl loses its water between useslook downstream at venting or a partial blockage. That one isn't a tank problem.
Rocking bowls, wax rings, and the flange underneath
A toilet that rocks isn't a nuisance, it's a countdown. Every small movement works the wax seal between the bowl horn and the closet flange, and once that seal opens, a little water and waste goes into the subfloor on every flush. You won't see it for a year. Then the flooring around the base darkens and the whole area feels spongy underfoot.
The flange is the collar that anchors the bowl to the drain, and it's meant to sit level with the finished floor. Old houses complicate that. In pre-1970 homes across Denver, Littleton, and Englewood, the flange is often cast iron with a rusted-through bolt slot. Remodeled homes have the opposite problem: someone tiled over vinyl, the floor rose half an inch, and now the flange sits below the finished surface. A wax ring can bridge a small gap. It cannot bridge that one.
The fixes are specific and they work. A stainless repair ring screws over a broken cast iron flange. An extender kit brings a sunken flange up to the new floor height. Shims plus fresh caulk are legitimate only when the flange itself is sound and the floor is what's uneven. Shimming a broken flange just quiets the rocking while the leak keeps going.
If the base has ever leaked, look underneath before anything gets reset. Wet particleboard doesn't dry back into a floor. In two-story homes around Parker and Highlands Ranch, a second-floor toilet leak usually announces itself as a ceiling stain in the room below, long after the wax ring gave up.
Repair, replace, and what a swap costs here
Nearly every internal problem is a repair, and a cheap one. A flapper costs a few dollars. A fill valve is usually under thirty. A full rebuild kit covers both plus the tank-to-bowl gaskets. Any of those beats a new toilet by an order of magnitude.
Replacement earns its keep in four situations: a cracked tank or bowl, since porcelain fails fast once it starts and no repair exists; a bowl that's been reset three times and still weeps; a 1980s water hog you're tired of feeding; or a remodel where the floor is coming up anyway. Front Range labor for a standard swap, assuming an accessible flange and a shutoff that closes, tends to land in the same few-hundred-dollar band as a faucet replacement, plus the toilet and the haul-away. A broken flange, a seized angle stop, or a tight second-floor bathroom moves that up.
Measure the rough-in before you buy anything, meaning the distance from the finished wall back to the bolt caps at the base of the bowl. Most homes are built around twelve inches. Older bathrooms in Denver and Longmont sometimes run ten or fourteen instead, and a bowl made for the wrong number never sits flat against the wall, whatever the salesperson promised.
We route quote requests and write these guides. Nobody here bills for a toilet, so there's no reason to push one on you. If the fix is a flapper and twenty minutes, that's what we'll tell you, and the rest of our fixture guidance is written the same way.
Repair the guts, replace the fixture. Tank parts are cheap, near-universal, and quick, so a running or slow-filling toilet almost never justifies a new bowl. Cracked porcelain, a rough-in you hate, or a third wax ring in five years is where replacement stops being an upgrade and becomes the cheaper path.
Need this handled this week?
Start a quoteChoosing a toilet that clears on the first flush
Low-flow toilets earned a bad name in the 1990s and then quietly got good. Modern 1.28 gallon models move waste better than the 3.5 gallon units they replace, because the engineering shifted from sheer volume to trapway geometry and flush valve size. Look for a fully glazed trapway and a three-inch flush valve instead of the older two-inch. That single spec is most of the difference between a confident flush and a plunger living beside the wall.
One corridor-specific caveat. In older neighborhoods with long, flat runs of cast iron building drain, and that's Denver's bungalow belt, Wheat Ridge, and north Englewood, less water per flush means solids travel slower through a pipe whose interior is already rough with rust. A high-efficiency toilet is still the right call. But if the house has a history of sluggish mains, get the line scoped instead of blaming the new fixture, and our drain cleaning guide explains what a camera actually shows.
Shopping notes worth having. Comfort height, roughly 17 to 19 inches to the seat, is easier on knees and now outsells standard height. Skirted bowls look clean and are harder to service later. One-piece toilets have no tank-to-bowl gasket to fail, which is one fewer repair over twenty years. And buy a brand whose flapper your hardware store stocks; off-brand flush valve seats turn a five-minute job into a scavenger hunt.
Check the seat bolts once a year and keep tablets out of the tank. That's the entire maintenance program.
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Questions we actually get
Toilet Repair & Replacement: quick answers
Is the water at the base of my toilet a leak or just condensation?
Both are common here. Condensation shows up in summer, coats the whole tank in a cold sweat, and dries by afternoon. A wax ring leak shows up right at the base, smells faintly, and comes back after every flush. Dry the floor completely, then flush a few times and watch the joint. Water that returns only when you flush is the seal, not the humidity.
Will a 1.28 gallon toilet clog more in an older house?
The toilet itself usually won't. Modern high-efficiency bowls clear a solid load on one flush when they have a three-inch valve and a glazed trapway. The old drain line behind it is the variable. If your cast iron branch runs long and flat with a rough interior, a new toilet can expose a problem that already existed. Scope the line before you blame the fixture.
Can I set a new toilet myself?
Plenty of people do. What trips DIY installs is the flange, the seal, and torque. Check that the flange is sound and sitting at the height of the finished floor, lower the bowl straight down without sliding it, since sliding smears the wax and ruins the seal, and snug the closet nuts a little at a time by feel. Overtightening cracks porcelain, and porcelain gets no second chance.
Running, rocking, or leaking?
Describe what the toilet is doing and name your city, and a real person will tell you whether it's a part or a replacement.
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