Measure a toilet's rough-in from the finished wall, not the baseboard, to the bolts; most are 12 in, some 10 or 14. For a faucet, count the sink holes and spacing: one hole, three 4 in apart, or three spread 8 to 16 in. Swapping either without altering the water supply or piping needs no permit in Duluth or Superior.
What to measure before you buy a toilet
The rough-in decides which toilets fit. Kohler's toilet buying guide says to measure from the wall, not the baseboard, to the floor bolts that hold the toilet down, and that 12 in is the most common rough-in, with 10 and 14 in also made. American Standard measures the same way, from the center of the bolt holes to the finished wall, and explains when the other sizes help: a 10 in model when the wall leaves no room for the tank, and a 14 in model when a 12 in toilet would leave a wide gap behind the tank. Measure before the store trip, not after.
Height and bowl shape come next. Kohler measures toilet height from the floor to the top of the seat, says most toilets fall between 15 and 19 in, and puts standard toilets under 17 in and chair-height toilets at 17 in or more, about 2 in taller.
If you're asking how tall a toilet should be after a hip replacement, ask your surgeon or occupational therapist; they'll tell you whether a chair-height toilet or a raised seat fits your recovery. Kohler lists elongated bowls at 28½ to 31⅝ in long and round-front bowls at 25⅝ to 29¾ in, so check the swing of the bathroom door before choosing elongated in a tight room.
| Measurement | How to take it | What it decides |
|---|---|---|
| Toilet rough-in | Finished wall to the center of the floor bolts, never the baseboard | A 10, 12 or 14 in model |
| Space in front of the bowl | Front of the bowl rim to the door swing, tub or vanity | Round-front or elongated bowl |
| Seat height you want | Floor to the top of the seat on the old toilet | Standard or chair height |
| Toilet seat | Bowl shape, round or elongated | Which seat fits the bowl |
| Faucet holes | Count the holes under the sink, including any hidden by a plate, and measure center to center | Single-hole, 4 in centerset or widespread |
| Shutoff valves and lines | Look under the sink and behind the toilet; note corrosion or crumbling rubber | Whether valves or lines get replaced too |
When a repair kit beats a new toilet
Most running toilets need a flapper or a fill valve, not a new toilet, and many parts sold as universal fit most toilets. The flapper is the one to get right, because it comes in two sizes. Fluidmaster's sizing guide says to measure the old flapper across: about 3 in across takes a 2 in flapper, and about 4 in across takes a 3 in flapper. Fluidmaster also sells one flapper made to fit both sizes when you can't tell. Take the old part to the store, or photograph the inside of the tank with the lid off.
Can you replace just the tank? On a two-piece toilet, the tank and bowl are separate pieces bolted together, so a cracked tank can be swapped, but the new tank has to be the one made for that bowl model, and a one-piece toilet has no separate tank at all. When the model is unknown or discontinued, a whole new toilet is often simpler.
There's no replacement schedule for a toilet, but age is a fair reason. Kohler notes that older toilets used 3.5 gallons per flush, while its current models use as little as 0.8. A cracked bowl, a toilet that rocks after the bolts are snugged, or a leak at the base are the signs it's time.
Making sure the new faucet fits your sink
Match the faucet to the holes. Kohler's bathroom faucet guide describes three common setups: single-handle faucets for sinks with one hole or a 4 in plate, centerset faucets for three holes 4 in apart, and widespread faucets for three holes 8 to 16 in apart. Kitchen sinks vary more, so count the holes, including one used by a sprayer or soap pump, before you buy.
Not every drip means a new faucet. Knobs and handles can often be replaced, and a leaking two-handle faucet usually needs a stem or cartridge; the part has to match the brand and model, so bring the old one to a plumbing supply counter. The aerator is the cheapest fix. EPA's WaterSense page says labeled bathroom faucets and accessories use at most 1.5 gallons per minute, 30% or more below the standard 2.2, and that a WaterSense aerator can cost as little as a few dollars. Replace it when it's crusted with minerals or the stream sprays sideways.
New supply lines come with the job. Fluidmaster's supply line instructions start with shutting off the valve, removing the old connector and cleaning the threads, then tightening the metal nut at the shutoff half a turn past hand-tight; the plastic Click Seal nut at the fill valve is only hand-tightened until it clicks, and Fluidmaster says the click means it's sealed. Our planning range for faucet replacement is $130–$260, plus the faucet, and it includes new supply lines and a leak test.
Permits, old shutoffs and how long it takes
In Duluth, swapping a faucet or toilet needs no permit as long as the water supply isn't altered; new plumbing brings a plumbing permit. In Superior, no permit is needed if the piping isn't altered. Moving a drain, adding a fixture or rerouting a supply line is done under the required permits. Our permit guide has both cities side by side.
Old houses add time at the valves and the floor. A shutoff that hasn't turned in decades may not close fully, and a toilet that rocked for years may have soaked the subfloor around the flange. We check the valves before the old fixture comes off. If the whole room is tired, what to expect in an older bathroom covers the bigger picture. Our planning range for toilet installation is $150–$300, plus the toilet, including haul-away of the old one. See faucet and toilet replacement for the full scope.
How do you measure a toilet's rough-in?
Measure from the finished wall behind the toilet, not the baseboard, to the center of the floor bolts. Kohler and American Standard both use that method, and 12 in is the most common size, with 10 and 14 in models for tighter or deeper spaces.
Then measure the room in front of the bowl to choose round-front or elongated, and the old seat height if you want a taller toilet.
Are toilet repair kits universal?
Many fit most toilets, but not all. Fill valves and flappers sold as universal cover a lot of tanks, yet flappers come in 2 in and 3 in sizes. Fluidmaster says to measure the old flapper across: about 3 in means a 2 in flapper, and about 4 in means a 3 in flapper.
Some toilets use brand-specific parts, so bring the old part or a photo of the tank's inside when you shop.
How do I know what faucet will fit my sink?
Count the holes under the sink and measure their spacing center to center. Kohler lists single-handle faucets for one hole or a 4 in plate, centerset for three holes 4 in apart, and widespread for three holes 8 to 16 in apart. Look for a hole hidden under the old base plate, and count any sprayer or soap pump hole.
How long does toilet replacement take?
A straight swap on a sound floor is usually a couple of hours: shutting off the water, removing the old toilet, setting a new wax ring and bolts, leveling it, connecting a new supply line and checking for leaks. A seized shutoff, a broken flange or a soft subfloor adds time, and that repair is priced before it's done.
Have a toilet or faucet to replace? Call or text (715) 919-7956 with a photo of the fixture and the valves underneath, or send the details. If a shutoff looks crusted or won't turn, say so, since it belongs in the price. You approve that written price before the water goes off, and our visit fee is waived when you do.
Next steps. For this kind of work, see our plumbing repairs page and How Much Does Toilet or Faucet Replacement Cost in Duluth, MN? Serving Duluth, Superior and beyond.
Keep reading: Paying for a Remodel in MN and WI: Loans and Medicare and Senior Bathroom Safety in Duluth: Heights, Curbless Showers.